Welcome! Ultralight backpacking is my passion, and keeping up on new technologies, gear, and techniques relevant to UL backpacking is what floats my boat. I'm always looking for the lightest, most functional gear to improve a lightweight or ultralight backpacking kit, and report my impressions and field testing results here. For hikers wanting to keep up on the latest and greatest ultralight backpacking gear, this is a good place to hang out. Also, there is a lot of information here (and on our informational website Southwest Ultralight Backpacking) on useful techniques and backcountry etiquette -- food for thought for hikers wanting to lighten their load and their impacts.

My goal for Ultralight Insights is to understand, test, and report on new technologies and gear of interest to lightweight and ultralight backpackers. It's a passion after all, so we just plain enjoy talking about it. I hope readers will add their own wisdom and comments, respond to my questions, ask their own questions, and correct me if I get something wrong. Happy hiking! Will

Wednesday, July 4, 2018

GEAR REVIEW: Osprey Levity 45 Backpack

By Will Rietveld

Lightweight Internal frame backpacks are getting lighter and better. Nowadays if you are looking for a lightweight internal frame backpack, you have several to choose from in the two pound range.

The Osprey Levity 45 and Levity 60 (and women’s Lumina 45 and 60) look to be excellent choices, based on initial impressions and their specifications. But initial impressions often lead to disappointment in the world of outdoor gear. So, how does the Levity perform in the backcountry?

The internal frame Osprey Levity 45, arriving spring 2018, is full-featured, size Large weighs just 1.927 pounds, and is capable of carrying a sizeable load. I opted to test the Levity 45 because it has sufficient room for my small gear kit, plus extra room for the food and water I need to carry on longer trips. Its brother, the Levity 60, has 60 liters of volume and weighs only a smidgeon more.  (Osprey Packs photos.)

 Specifications and Features

Osprey (www.osprey.com)
Levity 45 (Levity 60, and Lumina 45 and 60 are also available)
Size Large tested, 48 liters.
Arched 3.5 mm Lightwire 6065 aluminum alloy loop
SUL Airspeed tensioned backpanel with side ventilation, Exoform hipbelt and harness
Main fabric is 30D Cordura silnylon ripstop, abrasion areas are NanoFly 200D nylon x 200D Ultra High Molecular Weight Polyethylene (UHMWE)
Manufacturer specification 1.927 pounds (30.7 ounces), measured weight 30 ounces
Fixed top lid with zippered pocket, key clip, and attachment points; bellowed front fabric pocket; dual access fabric side pockets; sternum strap with whistle; Exoform hipbelt with ErgoPull closure; hydration sleeve with center hose port, load lifter straps; 2 daisy chains on front for additional attachment, drawcord side compression straps.


As you can see in the table above and photos, the Levity is full-featured. The only thing it does not have is hipbelt pockets, which I missed. Add-on pockets are available from various sources, like the one shown in the photos.

The design of the Levity and Lumina packs is similar to the Osprey Exos packs, only lighter. Although the Levity is light weight, it is constructed of durable fabrics. All of the pockets are made of 210 denier UHMWP described above.

Front and backpanel views. The Levity is characterized by a large kango pocket on the frontpanel (left) that holds a lot of stuff. The large side pockets begin at the daisy chains, and are accessible from the top and side. A traditional top pocket provides even more easy access to frequently needed items on the trail. All of the pockets are made of durable fabric instead of mesh. The trampoline backpanel (right) is another distinguishing feature. It's supported by a peripheral arched tubular aluminum frame that tensions the mesh backpanel away from the frame and pack body, providing excellent ventilation and form fit.

Side view. The tensioned backpanel and arched shape of the pack are more apparent in this view. Fabric side pockets are large, extenting from the blue daisy chain to the backpanel seam. I like to carry my hydration system in a side pocket for easier access. I counterbalance it with a tent in the opposite side pocket. Each side has a zig-zag drawcord compression system that works very well to firm the pack when its loaded, and compress the pack to a smaller volume to carry smaller loads.

Bottom view. Yes, the pack's white fabric gets dirty, especially on the bottom. It cleans up well however. The fabric covering the frame around the bottom is a high wear area, but there were no signs of wear from my testing. Durable fabrics and corner reinforcements help a lot, but it's entirely possible to wear holes in the pack's bottom edges from rough use. Note that the hipbelt pockets are my additions; the pack does not include any pockets on the hipbelt.

Field Testing

I tested the Levity 45 backpack on a February 9-day trip in the Grand Canyon following the “Butte Fault Route”, which is a rugged 80 mile mostly off-trail route crossing about 12 canyons. I also tested the Levity on several local backpacking trips in Southwest Colorado.

 Before my Grand Canyon trip I trained with the pack loaded with 30 pounds. It carried the weight well, and effectively transferred weight to my hips. However, with this amount of weight I noticed the hipbelt tends to slip down when I put it directly on my hips; it was necessary to tighten the hipbelt very tight to keep it in place. I found it carried a heavier load much better with the hipbelt on top of my hips, and adjusting the shoulder straps and load lifter straps to pull the pack’s top against my back.

On the Grand Canyon trip I started out with 27 pounds, and carried over 30 pounds at times when I needed to carry extra water. While the weight doesn’t sound that heavy, it was for me since I am normally an ultralight backpacker, plus the terrain was very challenging with many steep climbs and descents, dry wash boulder hopping, and class 3-4 scrambling. My opinion is 30 pounds is a reasonable upper limit for the Levity, and 20 to 25 pounds is the comfort range, on target for lightweight backpacking.

The trip was enough to shred a backpack, especially one with mesh pockets, but the Levity came out virtually unscathed. Its white color got a bit dirty, but I could only find a couple of minor scratches on the front pocket. That says a lot about the durability of this pack.

Since my gear kit is small and compact, I was able to get all of my gear plus 9 days of food into the pack, and carry for a full day. Granted, the pack was full, but it all fit. For a larger gear kit, the Levity 60 is a good choice, and weighs just a smidgeon more.

The Levity’s side compression system is excellent. It effectively reduces pack volume for smaller loads so one pack can be used for different trip lengths and load sizes. Here I am using the Levity as a day pack on a day hike from camp.

 There is a large hydration sleeve inside the main compartment, which is wide and nearly the full height of the pack. It’s big enough for a large hydration bladder or for storing gear like a flattened shelter or sleeping pad.

One consequence of the pack’s arched trampoline backpanel is it creates an hourglass shaped main compartment, meaning it’s narrower in the center. However, that’s only a minor inconvenience that’s overcome by fully releasing the side compression cords before filling the pack.

My only other dislike is the lack of hipbelt pockets. I missed them so much I added one for my pack testing. I really rely on hipbelt pockets to hold my compact camera, trail snacks, sunscreen, lip balm, and other small items I want with easy reach.

Summary of Product Pros and Cons

Things I especially like about the Levity are:
  • Its amazing light weight for an internal frame backpack
  • Trampoline backpanel is well ventilated
  • Fabric side pockets and front pocket, instead of mesh, are very durable
  • Front kango pocket holds a lot of gear and keeps it handy
  • It’s full-featured (but no hipbelt pockets)
  • Its available in men’s and women’s versions, two volumes, and three sizes, even a women’s size Extra Small
  • It fits very well and feels like I’m wearing it
  • It comfortably carries a substantial load, well within the range of lightweight backpacking
  • Large hydration sleeve will carry three liters or more, or can be used to carry a flattened shelter or sleeping pad
  • Easy ErgoPull hipbelt tightening
  • The side compression drawcords really work to effectively adjust pack volume, allowing one pack to suffice for different trip lengths and load sizes

Things I dislike about the Levity are:
  • No hipbelt pockets (I can add them on, but would rather have the pack come with them, big ones please)
  • Constriction in the center of the main compartment (but the form-fitting ventilated trampoline backpanel is worth it)


There are a growing number of internal frame backpacks in the two-pound range nowadays, but the Osprey Levity/Lumina packs stand out for several reasons. First, they are true internal frame backpacks, meaning the frame is built-into the pack, allowing the pack to fit, transfer weight, and carry comfortably. Some of the other packs in this category have a removable frame that does not do the job as well.

Second, Osprey gets everything right – design, materials, features, and fit. The Levity’s success comes from Osprey’s mastery of pack design, a super lightweight frame and backpanel, putting the right fabrics in the right places, and incorporating essential features (except hipbelt pockets). The 210 denier UHMWE nylon fabric used in high wear areas is sometimes called “ballistic nylon” or “military grade nylon” and is super strong and abrasion resistant, which I verified.  The Levity and Lumina packs have a total of 12 combinations of gender, volume, and pack size. The Lumina even has an Extra Small size.

And third, the packs’ side drawcord compression system is simple, very lightweight, and really works. I had no trouble using the Levity 45 for a 9-day extended trip, an overnight trip, or as a day pack. The compression works that well. The Levity (and Lumina) is one of the few packs I have reviewed (and I have reviewed many) that I can say one pack does it all. In this case I actually recommend getting the 60 liter version, if you will actually need 60 liters sometimes. It weighs only a fraction more than the 45 liter size, and the compression system will adjust it to nearly every need. I chose the 45 liter size because that’s as big as I will ever need.

The feeling I have after testing the Levity is “why would anyone want to carry a heavier pack with the same volume”? Heavier packs carry a heavy load more comfortably, but why carry a heavy load at all? The Levity is a good way to save 2-3 pounds and not miss anything. And it’s a good incentive to reduce the weight of everything else in your pack, which is easy to do with judicious choices from today’s wide array of lightweight gear.

Sunday, July 1, 2018

GEAR REVIEW: Big Agnes Insulated AXL Air Sleeping Pad and Pumphouse Ultra Sleeping Pad Inflation Pump

By Will Rietveld

Definitely for lightweight backpackers, and even for ultralighters, a comfy sleeping pad is a comfort item to spend a few ounces on in order to get a good night’s sleep.

The specs for the new Big Agnes AXL pad, coming out spring 2018, sound really good – weight as little as 9.6 ounces for a full-length, mummy-shape, 3.25-inch thick (that’s correct) inflatable sleeping pad. That’s down right plush!

The lightest of their AXL family of pads is the uninsulated mummy version, measuring 20x72 inches and weighing 9.6 ounces. That’s the one I tried to get for testing, but it wasn’t available, so I settled for the insulated rectangular version (shown) weighing 11.9 ounces.

What is remarkable about this pad, compared to the competition, is its thickness and lightweight. It’s lighter than the full-length Therm-a-Rest Neo-Air XLite pad and much thicker.

So, given all these good numbers, how does the AXL pad perform for lightweight backpacking?

Specifications and Features – Sleeping Pad

Big Agnes (www.bigagnes.com)
Insulated AXL Air Sleeping Pad (rectangular insulated version tested)
“lightweight double-ripstop nylon with aviation grade TPU lamination”, Primaloft Silver insulation with reflective film
20x72x3.25 inches; outer tubes are 3.75 inches
Mfr specification 11.9 ounces, measured weight 12.4 ounces (pad only)
Single 2-way valve, interior antimicrobial treatment, quick deflation valve, micro-release button for inflation adjustment, larger outer chambers to cradle sleeper
Sizes Available
Regular, wide, and mummy; insulated and uninsulated
Pad, stuff sack, repair kit

Specifications and Features – Inflation Pump

Pumphouse Ultra Sleeping Pad Inflation Pump
Ripstop nylon
19.5x13.5x8 inches
Mfr specification 2.9 oz, measured weight 2.55 ounces


The AXL inflatable sleeping pad is available in Regular (20x72 inches), wide (25x72 inches), and Mummy (20x72 rounded and tapered ends). Shorter lengths are not available, and would not work well because of the pad’s thickness.

Insulation is Primaloft Silver synthetic, plus a reflective film. Big Agnes prefers to provide a temperature rating (15F), rather than play the R-rating game. Remember that number. The uninsulated pads are grey and the insulated pads are red.

The Pumphouse Ultra Inflation Pump is a pump bag with a fitting that pops into the inflation valve on the sleeping pad. It’s claimed to fit other Big Agnes pads as well as traditional valves. It works as follows: attach the outlet to the pad’s valve, open the sack so it fills with air, fold the top over, and roll the bag toward the pad.

Field Testing

I tested the AXL pad on spring backpacking trips in southern Utah and summer backpacking trips in the southern Colorado Mountains. Nighttime temperatures were as low as 27F.

Inflating the pad by mouth requires about 30 deep breaths, which is quite a bit of effort. Using the Pumphouse inflation bag is much faster and easier, and it doesn’t introduce moisture into the pad. I found the pump bag easy to use, and it gets easier as you learn the technique. I tested the Pumphouse bag on a conventional inflation valve and did not find it to work as Big Agnes claims. The pump bag effectively doubles as a stuff sack, but I don’t see how it can be used for a portable shower as claimed.

I like its large, one-way inflation valve because air does not leak out between blows. The micro-release button is inside the cap of the valve; after the pad is inflated, simply press on the flap and release a little air to get the desired firmness.

The AXL pad is quite durable, so this is not an ultralight pad that will require frequent patching. And Big Agnes provides a patching kit just in case.

The plus side of the AXL pad is its amazing comfort. I never expected to put the words “3.25 inches thick”, “comfortable, and “lightweight” in the same sentence but Big Agnes pulls it off. This pad is like floating on a cloud; made in heaven for lightweight backpacking, and some ultralighters may adopt it too.

The minus side was a big surprise to me – even though the pad I tested is insulated, I found the pad to be cold at temperatures below 40F. Specifically, my bottomside got chilly, enough to inhibit sleep. My observed threshold of around 40F is a big difference from the claimed 15F comfort rating.

 I verified that the chill problem was indeed the pad by placing a blanket over the pad and sleeping on that combination on a similar sub 40F night; I had no problem staying warm in the same bag, clothing, and shelter.

Note that that my observed 40F comfort threshold is for me; other sleepers may experience discomfort at cooler or higher temperatures, and hotblooded sleepers may not experience any discomfort at all.

To investigate the issue, I peered into the inflation valve opening to see what’s inside, and couldn’t see any insulation. Next I held the pad in front of a strong desk light and found that the pad is insulated with a thin sheet of synthetic insulation bonded to the upper pad fabric, and the insulation sheet has large oval holes (2x3 inches) in it so it doesn’t interfere with top/bottom fabric welds that determine the pad’s thickness and texture. Note in the photo below that the insulation has some rather large thermal leaks in it.

This photo of the pad with backlighting shows a thin insulation sheet inside bonded to its upper surface. The insulation has large oval cutouts to allow room for top/bottom fabric welds to create the pad’s thickness and texture. The inflation valve is at the upper left.

My conclusion is the AXL pad’s insulation is insufficient to meet its claimed comfort rating, for me at least. It’s thin with large holes in it, and is not very effective.


By my testing, I found the AXL pad to be a mixed bag. On the one hand it’s very comfortable. However, it’s overweight by a half ounce, and its warmth (for me) is nowhere near the claimed 15F. The problem was consistent; whenever the nighttime temperature dropped below 40F I got chilly on my bottomside. Note that the insulation in a sleeping pad works in much the same way as an insulated jacket; rather than feeling a cold line where the jacket is stitched or the pad insulation has a cutout, you feel an overall warmth or coolth. More thermal leakage means less warmth. In the case of the AXL pad, the uninsulated area due to incomplete coverage of the pad's topside plus numerous large cutouts allows a lot of thermal leakage, so more coolth. 

Because of this shortcoming, I consider the AXL Air pad, in spite of its insulation, to be a summer only pad when used by itself.

One solution to make the AXL pad warmer is to carry a thin foam pad to place over it to provide extra insulation when it’s needed. The one-eighth inch thick Gossamer Gear ThinLight pad (2.4 ounces/$18) is a good choice. It’s full-length, stays in place over an inflatable pad, and has numerous other uses. I have tested the ThinLight to extend the warmth of other sleeping pads, and found it adds a remarkable amount of extra warmth for its minimal weight.

However, when you add up the actual weight of the AXL pad, the Pumphouse inflation bag, and a supplementary ThinLight pad you arrive at 17.4 ounces, which substantially reduces the lightweight appeal of the AXL pad.

One consideration for campers who use a shelter with limited headroom is the thick AXL pad will reduce headroom even more. In other words, the AXL pad works best in a tent with plenty of headroom.

In my opinion, the AXL pad is too heavy for ultralight backpacking, so I will reserve it for lightweight backpacking, base camping, and car camping. Lightweight backpackers will love it for its exceptional comfort and reasonable weight. And there should be no problem with late night chills on warm summer nights.

I would appreciate reader comments on their experiences with this pad. Does your bottomside get chilly late at night when the temperature hits its low? And about what temperature does that occur? Or perhaps you don’t find any issues at all. Share your experience below.

Monday, March 26, 2018

GEAR REVIEW: TOPO Athletic Runventure 2 Trail Running Shoe and Gaiter

By Will Rietveld

As I have often mentioned, my preference for a backpacking shoe is a lightweight trail runner with a wide toebox, snug heelcup, all-synthetic upper with welded construction, good midsole cushioning, rock plate, and an aggressive outsole for good traction.

That said, I know that footwear is a very personal thing, everyone has different preferences, and different hiking conditions call for different footwear.

In general though, when you carry a light back, you can also wear light shoes, which get the job done just as well as the heavier clunkers, and save a lot of energy.

The main reason I love a wide toebox is because I have wide feet, but beyond that it’s important to note that, as the miles mount up, whether you’re a runner or a hiker, our feet swell and it helps a lot to have a wide toebox to accommodate the expansion.

The new Topo Runventure 2 Trail Running shoe weighs just 9.2 oz/shoe for men’size 9 and has all my desired features for lightweight and ultralight backpacking. (Topo Athletics photo.)

Specifications and Features

Topo Athletic (www.Topoathletic.com)
Runventure 2 Trail Shoe and Topo Gaiter
Nylon mesh upper with TPU overlays, EVA midsole, rubber outsole
Roomy toebox, snug heelcup, padded tongue and heel, moderate cushioning, rock plate, grippy outsole, zero drop.
9.2 ounces/shoe (men’s 9); 11.1 oz/shoe for tested men’s 12. Size L/XL gaiter weighs 1.25 oz/pr
Shoes $110, Gaiters $20


The above table provides most of the relevant information describing the shoes. Compared to the Terraventure shoe the Runventure 2 is a bit lighter (1.2 oz/shoe less), is zero drop compared to a 3 mm heel rise, has less cushioning, and has a bit less stability control. The upper and stiffness are similar.

The Runventure 2 shoe is zero drop, meaning no heel lift. That platform is preferred by many runners, but preferences run the gamut, and most running experts emphasize that a conditioning period is necessary to adjust to zero drop shoes. I note that the Topo Terraventure and Hydroventure shoes, which I have previously reviewed, have 3 millimeters of heel lift. Over time my feet have adjusted to these flatter platform trail runners, and I have no problems with them, although I don’t see any particular advantage of using them for hiking and backpacking compared to conventional shoes.

I tested the Topo Gaiter with the Runventure 2 shoe. The gaiters are made of a stretch nylon fabric that is very durable. They attach at the front with a conventional lace hook, and at the rear with a pair of unique hooks that insert into channels at the back of the shoes. (Topo Athleetics photo.)


 I wore the Runventure for day hiking, trail running, and backpacking on a total of 23 outings totaling 39 days. 

I used them mainly on rocky trails, but there were some notable exceptions which included some off-trail day hikes and a 9-day 78 mile traverse in the Grand Canyon which involved backpacking in very rough and steep conditions.

I have wide feet and find the Runventure just barely wide enough for me when worn with thin socks.

The Runventure performs superbly on trails, providing great traction, cushioning, and agility. Actually, the Runventure is remarkable in that such a lightweight shoe can provide so much foot protection, comfort, and trail performance.

For most of my testing, on trails, I found the Runventure to be very durable for their light weight. This is, of course, the intended use for the shoes. The welded upper with TPU overlays helps a lot for this.

However, one 9-day mostly off-trail backpacking trip in the Grand Canyon shredded them pretty well, as shown in the above photo. I hiked through steep talus slopes and brush, and did a lot of class 3 and 4 scrambling in them while carrying a backpack, and it all took its toll. Note the holes in the mesh uppers on the sides of both shoes; I have found that to be a vulnerable area for shoe damage.

The Topo Gaiter stayed put and kept debris out of my shoes while trail hiking, but it was a different story while hiking off-trail. 

I found the gaiters were not tight enough over the top opening of the shoe to keep debris out, and the hook-in-hole gaiter attachment at the back of the shoes frequently came loose. The heel attachment is simply too cumbersome. Most of the time I left the gaiters attached to the shoes and slipped my foot through the gaiter first and then into the shoe; still too cumbersome. I would be happier with a simple hook-and-loop attachment at the heel, and a tighter fit over the top of the shoe.


Overall, the Runventure 2 has all the features and performance I desire for a good trail running, trail hiking, and ultralight backpacking shoe on trails. However, this shoe just doesn’t have enough beef and durability for off-trail hiking (which is not their intended use). I like the Topo Terraventure better for that purpose, although I wore holes in the sides of them too.

It would be nice if Topo would develop a beefier shoe that can take the abuse of off-trail running and hiking, something akin to the New Balance Leadville or Montrail Hardrock. These of course would weigh a bit more, but Topo designers are experts at packing a lot of performance into minimal weight.

I note that a lot of lightweight and ultralight backpackers prefer Altra shoes, the Lone Peak in particular. The Lone Peak has most of the same attributes as the Topo trail runners, and is somewhat beefier and more durable. They weigh a bit more too, 12.2 oz/shoe versus 10.4 oz/shoe for the Terraventure in my size 12. The uppers on the Lone Peak are a very durable nylon mesh, but they are stitched, which is not my preference. The side seams on the Altras have also opened up from my off-trail use.

Bottomline, for trail use, Topo nails the feature set that I consider to be ideal, and I highly recommend both the Terraventure and Runventure for lightweight hiking and backpacking on trails and less punishing off-trail use. However, they don’t have the beef (stiffness, cushioning, durability) for hardcore off-trail hiking.

Sunday, February 18, 2018

GEAR REVIEW: Patagonia Nano-Air Light Hybrid Jacket

By Will Rietveld

I reviewed the Patagonia Nano-Air Jacket a year ago and found the jacket’s active exertion comfort range occurs at temperatures lower than I normally encounter. In other words, it is more insulation than I need in my location for high exertion activities. Granted, it is a very attractive, and warm, jacket for less active endeavors.

Still wanting to test the concept of “breathable insulation”, I opted to next test Patagonia’s Nano-Air Light Hybrid Jacket, which is a lighter weight version of the Jacket.

Here’s the stats: the Nano-Air Jacket has 60 ounces/square yard polyester insulation, while the Nano-Air Light Hybrid Jacket has 40 ounces/square yard insulation, one-third less.  The fabrics in the two jackets are very similar.

The whole idea behind these jackets is to provide extended range comfort and avoid overheating during aerobic outdoor cool weather activities. So, how does the lighter weight Nano-Air Light Hybrid Jacket perform in active exertion conditions?

Specifications and Features

Patagonia (www.patagonia.com)
Nano-Air Light Hybrid Jacket
Outer shell is 1.3 oz/sq yd nylon ripstop, lining is 2 oz/sq yd nylon plain weave, both with stretch and DWR
Frontside fabric: 40 CFM, backside fabric 130 CFM
40 oz/sq yd Full-Range polyester
Size men’s Large tested: measured weight 10.85 oz; mfr specification 10.1 oz for size Medium
Full-height front zipper, slim fit, stretch fabric, wind-resistant frontside fabric, breathable backside fabric, 2 zippered handwarmer pockets, elastic hem and cuffs, thumbloops


The Patagonia Nano-Air Light Hybrid Jacket is designed to be a high performance garment. Patagonia’s synthetic Full-Range polyester insulation is analogous to Polartec Alpha, which is a “breathable insulation” meant to keep you comfortable during aerobic activities in cool temperatures, and provide an extended comfort range.

The frontside of the jacket is insulated and has a tighter weave shell fabric to provide some wind resistance (40 CFM); the backside of the garment is uninsulated and has a knitted weave to provide greater breathability (130 CFM). Both the shell and lining have a DWR finish, which I previously tested to be very effective.

Close up of the insulated frontside and knitted backside.

Field Testing and Performance

I tested the jacket on 20 outings consisting of day hiking, snowshoeing, cross-country skiing, backcountry skiing, and backpacking. Testing was mostly done in cool temperatures ranging from 15 to 40F.

Fit – Excellent, as I have found with all Patagonia garments. The garment’s body is extra long to cover the butt, and the sleeves are longer too. Its slim cut makes it fit closer to my body, so it’s not bulky, and layers well.

Features – The hand pockets are nice and roomy, and zip for security. I like the stand-up collar to provide some sun protection for my neck. The thumb loops are handy to donn the jacket over a baselayer or other garment.

Wind-Resistance – The tighter front fabric provides needed wind resistance so a cold wind does not readily penetrate.

Breathability – The frontside fabric does allow for some air exchange; it’s basically a trade-off between wind resistance and insulation. The backside fabric is much more breathable, but it is often mostly covered by a day pack or backpack. Breathability is maximized in activities like running, bicycling, and cross-country skiing where one does not normally carry a pack.

Performance – The graph below tells a lot about the jackets performance while speed hiking an undulating trail, carrying a daypack, in temperatures ranging from 25 to 30 F and calm air. The test was done before sunrise to avoid sun warming. I recorded the temperature and relative humidity inside the jacket with a Kestrel 4000, located at mid-chest, at 10 second intervals.

Test data for Patagonia Nano-Air Hybrid Jacket

Note that the jacket’s insulation maintained a fairly constant internal temperature in the 65 to 70 F range, which is good. However, humidity steadily built up inside the jacket as I hiked, and flattened out at about 65%. That indicates that the jacket’s fabric breathability was not enough to exhaust the moisture, allowing it to build up.

In terms of perceived comfort, it took about 45 minutes for the humidity inside the jacket to build up to the point where the jacket felt somewhat steamy inside and time to open the front zipper to increase ventilation.

But that is only part of the comfort story, because the test was done without any influence from the sun. I live in the Southwest US, where we get a lot of sun, and the sun is warm even in the winter. Thus the radiant heat from the sun has a big influence in jacket comfort, even in cold air. There were many occasions when I simply had to take the jacket off because it was too warm, when the air temperature was in the 30s and 40s F.

Issues – I found that the jacket’s fabric gets dirty fairly easily, as evidenced by the ring around the neck (from sunscreen) in the photo. And the photo was taken after laundering the garment. Also the jacket incurred some abrasion damage from a skiing fall, so it requires careful use.


Although the Nano-Air Light Hybrid Jacket was often too warm for me in the sunny Southwest, I found its sweet spot is cool, overcast, and breezy conditions, which is what the jacket is designed for. When I had those conditions, the jacket performed well for maintaining comfort over an extended range. In locations where it is overcast or breezy much of the time, or the sun is low, this jacket is capable of providing comfort over an extended range of conditions, as claimed.

The more consistent conditions are – namely overcast, cool, and breezy – the better this jacket will perform. Then all is good. The problem I found is variability; when the sun comes out or the wind stops, I get too hot. Opening the front zipper regulates comfort to some extent, but eventually it is not enough. The Nano-Air definitely provides some extended comfort, but the end result is usually the same – the jacket has to come off. 

Bottom line, it’s a very attractive, great fitting, hi-tech jacket that helps to provide extended comfort in cool, overcast, breezy conditions, but in my situation those conditions don’t exist for very long. If you exercise where those conditions are more typical, then this jacket is for you. However, don’t expect a silver bullet, the breathability part is subtle.

GEAR REVIEW: Crescent Moon Eva All-Foam Snowshoes

By Will Rietveld

This is a new snowshoe with no metal in it; it’s made of EVA foam, the same stuff used for cushioning in the midsole of athletic footwear. It’s received numerous awards for innovation, which is well deserved. It’s fairly light weight at 3.5 pounds per pair, which is true compared to many conventional snowshoes that weigh over 4 pounds per pair.

The new Crescent Moon Eva All-Foam Snowshoe is made of dual-density EVA foam; there is no metal in them. The bottomside has a tread molded in that makes a track in the snow like a snow tire. A hard plastic plate with spikes in inlaid into the bottom of the shoe for climbing traction.

And they certainly attract attention, as was the case when I tested the Eva All-Foam Snowshoes with experienced snowshoeing friends. They all asked how well they perform – traction on uphills, downhills and sidehills – and how do they feel without a binding hinge. That’s what I wanted to know too, which was my reason for testing this unusual snowshoe.

First a little background: I have been testing snowshoes for 14 years, and have published numerous reviews and articles on snowshoes in Backpacking Light Magazine during my 10 year tenure there. I snowshoe with a bunch of hardcore seniors who love to make their own trail through rough, steep, and very scenic terrain. So we know snowshoes, and that’s why my companions were so inquisitive.

So, how did these Eva All-Foam Snowshoes perform in different types of terrain and snow conditons? Read on.

Specifications and Features

Crescent Moon (www.crescentmoonsnowshoes.com)
Eva All-Foam Snowshoe
EVA foam and hardened plastic.
Embedded adjustable hypalon over the foot and heel straps with hook and loop closure
8 in x 24 in
Measured weight 3.5 pounds, mfr specification 3.5 pounds


The topside of the snowshoe is a softer EVA with the binding embedded. The bottomside is a molded harder EVA with a traction tread molded in plus an inlaid hard plastic plate with sharp spikes.

These snowshoes are definitely a new concept; some details: 

  • They are made of dual density molded EVA foam that is flexible.
  • The upper layer of the foam (white) is softer and has the binding anchored into it, so it’s not removable or replaceable.
  • The bottom layer of EVA is harder and has a traction tread molded into it, like a snow tire.
  • A hard plastic traction panel sporting 10 clusters of three-pronged spikes is inlaid beneath the binding, which serves the function of crampons in a traditional snowshoe.
  • The snowshoe does not have a binding hinge; instead it has lots of rocker (curvature) and flexibility to facilitate walking.
  • Since there is no binding hinge, the tail of the snowshoe does not drop when you lift your foot; rather the snowshoe stays flatly attached to the bottom of your boot.
  • The foam construction makes the snowshoes somewhat lightweight at 3.5 pounds, but they are not as light as they look, and certainly not the lightest ones to be found.
The simple binding is made of Hypalon rubber. Two adjustable top straps and one heel strap fit boots from a women's 7 to a men's 14. The underheel strap at the back is my gaiter strap.

There is no doubt that these snowshoes are unconventional, but how do they compare to conventional snowshoes? And are they any better?

Testing and Performance

I obtained a pair of the snowshoes for a few weeks to test them out, and had the opportunity to try them out in shallower snow, wet snow, and deep snow.

My first impression, in shallow (12 inches deep) and wet snow, is they feel the same as conventional snowshoes, which is remarkable since I was expecting some sort of adjustment to them. They walked, climbed, descended, tracked, and gripped as well as conventional snowshoes. They broke trail just fine. I did not have any icing up problems when I went from wet (open sun) snow to cold (shade) snow.  The peripheral lugs in the bottom tread gave the snowshoes good lateral stability. I had a hard time finding any fault with them.

Then I tested them on deeper softer snow (30 to 36 inches deep), and discovered their limitations. When following a few snowshoers who created an 8 to 10 inch trench, I sank in much deeper – these snowshoes lack adequate flotation for softer snow. Exacerbating that problem, the flat attachment of the snowshoes makes then act like scoops – snow  piles up on top of the snowshoes, which I have to lift when I pull them up out of the holes. They are laborious to use in soft snow, and forget about breaking trail with them in deeper soft snow.

I noticed after using the snowshoes on three all-day hikes (there were used some before I got them)  that the hard plastic spikes on the bottom are already rounded off, making one wonder about the longevity of these snowshoes. There is no noticeable wear in the molded EVA tread. Note: I did not walk on rock or pavement with the snowshoes, although I did walk on hard ice and hit an occasional rock buried in the snow.


I found from my testing that the Crescent Moon Eva All-Foam Snowshoes are best described as an entry level or beginner snowshoe best suited for packed trails. If you are making your own trail with a group of people, you want to be near the end of the line.

In soft deeper snow, because of their teardrop shape, they lack the flotation of other snowshoes the same length. Added to that, their flat position loads them with snow, making them laborious to lift. Overall, they are very unsuitable for breaking trail, or following a few others on a newly broken trail.

The hard plastic spikes on the bottom allow these snowshoes to climb quite well in firm snow, and I did not find the lack of a pivot point to be a limitation. When I am steeply climbing I concentrate my weight on the toe crampons of conventional snowshoes, but I found the spikes on the foam snowshoes seemed to function as well. However, the spikes are getting rounded off after only a few trips with normal wear and tear, which makes me wonder what the longevity of these snowshoes will be. Conventional snowshoes, with metal crampons, will last a long time.

Version 2 of the Eva All-Foam Snowshoe is coming in fall 2018 (right). It will add aluminum crampons to make them climb better, with no weight gain. Also note that the molded tread is revised too. Looks like they won't be all-foam anymore. The aluminum crampons should help with both traction and longevity. The current version is shown in the left photo.

The Eva Foam snowshoes cost less than most conventional snowshoes, and weigh a bit less, but I believe the old adage applies “you get what you pay for”. For example, the MSR Lightning Trail snowshoe in a 25-inch length weighs 3 pounds 6 ounces (2 ounces less), has a metal frame and crampons, provides serious traction in all directions, and costs $220 ($60 more). That’s where I would put my money, but I'm more of a hardcore snowshoer.

It's important to evaluate these snowshoes for what they are -- less expensive snowshoes for beginner and intermittent snowshoers who mainly travel on packed snow. They are simpler to put on and use, with no learning curve; simply walk on them. And for that niche they are a good choice. They are unique, simple and easy to use, function very well, and attract a lot of attention.