First Look: Gossamer Gear 2014 Mariposa Backpack – New Fabric and Lots of Nice Upgrades

By Will Rietveld

The Gossamer Gear Mariposa, their largest volume backpack at 70 liters, first appeared in 2004. Now, in August 2014, Gen 4 will arrive. It has come a long way. One can compare it with the evolution of a trend-setting car model, like the Toyota Prius. We are now in Gen 3 of the Prius, with each new generation dazzling us with advanced design, new technologies and features, better performance, more comfort, and more reliability. But the basic concepts have not changed. The Mariposa follows this same evolution.

Mariposa Genealogy

The original Gen 1 Mariposa was constructed of silnylon, featured two carbon fiber arrow shafts in sleeves on the backpanel to enhance weight transfer, and allowed the user to pad the 4-inch wide shoulder straps and hipbelt with clothing (or use provided lightweight foam pads). The outside pockets were all mesh. The measured weight (size Medium) was 17 ounces.

Then came the Mariposa Plus (Gen 2) constructed of a more durable grey ripstop nylon. It retained the straight carbon fiber stays, stuffable shoulder straps and hipbelt, and mesh pockets. Measured weight was 20.5 ounces.

The 2012 Mariposa (Gen 3) made further advances by introducing Gossamer Gear’s 140 denier Dyneema Gridstop pack fabric, a one piece contoured aluminum stay, a new Over-The-Top closure, fabric side pockets, and eliminating the option of stuffing clothing in the shoulder straps and hipbelt, while retaining their wide width. Measured weight is 28 ounces.

Now, in August 2014, the latest (Gen 4) Mariposa debuts, which is the subject of this article. How has it changed, and how much weight has been added?

What’s Different?

The new Mariposa is an upgrade, not a makeover. The pack has the same dimensions, volume, sizes, and basic features. There are a few bigger changes and lots of smaller ones. Overall, the new Mariposa is more elegant, professional, and refined.

The main changes are:

• The Mariposa is now constructed of Robic fabrics; the previous 140 denier Dyneema Gridstop exclusive to Gossamer Gear will be phased out.
• An internal hydration sleeve with two hose ports has been added.
• The shoulder straps are narrower and thicker, with spacer mesh on the inside.
• The hipbelt is wider and thicker, also with spacer mesh.
• New stretch mesh on the pad sleeve and front pocket.
• A trekking pole holder has been added to the front of the pack.
• Webbing cinch straps replace the cord/buckle to hold down the top cap.
• Cord loops are added to zipper pulls on the hipbelt pockets and top cap pocket.

So how do these changes affect pack weight? Not much; by my scale the pre-production Gen 4 Mariposa is only 0.9 ounce heavier than Gen 3; size Medium weighs 28.9 ounces without the external bungie system.

Fabric Changes – What is Robic?

As you can see, the 140 denier Dyneema Gridstop fabric of Gen 2, which was touted as “the ideal lightweight backpack fabric”, has been replaced in Gen 3 by Robic fabrics. Robic, made by South Korea’s Hyosung Corporation, is designed for applications where very high resilience and durability are needed. It surpasses Nylon 66 in tensile strength, tear strength, puncture resistance, and abrasion resistance. According to the manufacturer, this fabric is 100% high-tenacity nylon that can easily retain its original exterior even after long periods of use. The "old" Dyneema Gridstop contains super strong Spectra fibers in a grid pattern, but the rest of the fabric is ordinary Nylon. Bottom line, Robic is more durable than Gen 2’s 140 denier Dyneema Gridstop, lighter weight, and more cost effective. Gossamer Gear uses 100 denier Robic in the body of its new packs and 100x200 denier Robic in abrasion areas.

Photo Tour of the Gen3 Gossamer Gear Mariposa

The backpanel view shows the Mariposa’s new narrower, thicker shoulder straps, which are more female friendly. The new ones are 2.5 inches wide and 5/8-inch thick, replacing the 4-inch wide ¼-inch thick straps that was too wide for some people. The hipbelt is now 4.5 inches wide and ½-inch thick, replacing the previous 4-inch wide ¼-inch thick belt. The pad sleeve mesh is a bit lighter weight and a looser stretch. The sternum strap is nicer webbing then before and the whistle is gone.

The frontpanel view shows the new webbing straps (blue) to snug down the top cap, new mesh on the front pocket, and trekking pole holders (lower left).

The left side of the pack still has a large, tall pocket.

The right side has two pockets as before. Overall, the four outside pockets will hold a lot of gear and clothing.

The Over-The-Top lid is retained. The zipper pull on the top pocket, and hipbelt pockets, now have a cord loop that is easier to grab.

Bottom view. The SitLight pad provided with the pack overlaps the hipbelt, providing a padded lumbar area.

Close-up of the new narrower/thicker shoulder straps, which are identical to the ones on the new Gorilla backpack.

Close up of the spacer mesh on the inside of the new hipbelt. The new belt is wider and thicker than the previous one, and is interchangeable with the Gorilla.

The attached hipbelt pockets are the same size as the previous version; cord loops have been added to the zipper pull to make them easier to open.

The outside pockets on the Mariposa will swallow a lot of gear. My entire gear kit will fit in the outside pockets of this pack.

Even the “smaller” side pockets on the Mariposa are big and will hold a lot of gear.

First Impressions

Based on my experience with previous generations of the Mariposa, and my testing of Gen 4 so far, following are my initial impressions:

• Pack Weight. On my scale, the new pack weighs 28.9 ounces in size Medium. That is a gain of only 0.9 ounce (based on measured weights) from Gen 3, which is extraordinary considering the changes (mostly additions) made to the pack.
• Materials. The new Robic fabric is impressive, and its specifications indicate it should outperform the previous 140 denier Dyneema Gridstop. This is one of the first applications of Robic fabrics in backpacks, so it needs some time to develop a track record. Switching to lighter weight Robic fabrics was the key factor to offset the weight gain from adding several comfort and convenience upgrades.
• Refinement. The new Mariposa really looks professional and dialed in for the lightweight backpacker. The word “Spartan” no longer applies. The new Mariposa provides loads of volume, comfort, utility, and convenience for a sub-2-pound backpack.
• Utility. This is a very functional backpack, with a total of seven external pockets to organize your gear and make it readily available on the trail without having to dig into the interior of the pack. The three fabric side pockets and mesh front pocket will hold a huge amount of clothing and gear.
•  Pack Volume Compression. The Mariposa does not have any traditional side compression straps (as the new Gorillia pack will have). Rather, as with previous generations, an external elastic cord compression system for the front and/or sides of the pack is provided, which basically squeezes the pack to a smaller size. For a discussion of this issue, read my article LightweightFrameless Backpacks State of the Market Report 2011: Part 1 – Choosing andUsing a Frameless Pack. On the Mariposa, the asymmetric side pocket design (a tall pocket on one side and two shorter ones on the other) makes it very difficult to add conventional side compression straps without interfering with the pockets.
• Frame. The Mariposa has a removable inverted U-shaped, contoured aluminum stay that slips into sleeves on the backpanel. For its light weight, the contoured stay contributes a lot for transferring weight, retaining pack torso length, and contouring the pack to the user’s back. The Mariposa is a big pack (70 liters), and filling that entire volume usually adds up to a weight of 25-30 pounds or more, so the Mariposa needs an appropriate frame to effectively transfer that weight to the hips. In my limited testing carrying 20 pounds, I found the new Mariposa’s improved suspension system, in combination with the removable stay, helps a lot with weight transfer and carry comfort. 

 Important Tip for Pack Selection

• When comparing Gossamer Gear packs, many buyers will notice that the new Mariposa backpack weighs only slightly more than the new Gorilla, so they will reason “why not get the Mariposa so I will have plenty of volume when I need it, and the cost is not much different either.” Don’t do it!! Unless you really need a large volume pack, you are much better off choosing a pack that matches the volume of your gear kit plus room for 5-6 days of food (see the above referenced article). The Mariposa lacks a good pack volume compression system, so it will not carry that well when partially full. It is far better to choose a smaller volume pack, like the Gorilla (which has good compression), that will be closer to full most of the time, and compressed, compared to carrying a larger volume pack that is not full most of the time. Bottom line, many people overestimate the pack volume they need; its best to take the time to accurately determine the pack volume actually needed (its usually smaller than you think) and avoid the error of purchasing a pack that is too big.