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, August 20, 2014

First Look: Gossamer Gear 2014 Gorilla Backpack – Some Nice Improvements to an Already Outstanding Pack

By Will Rietveld

At 46 liters, the Gorilla is a medium volume pack suitable for hikers on the upper end of ultralight or the lower end of lightweight, in other words a base weight between 8 and 12 pounds. It’s intended for loads in the 15 to 25 pound range, and optimally in the 15 to 20 pound range.

When I reviewed the original Gorilla for Backpacking Light Magazine in 2009 I gave it a Highly Recommended rating. Now, in August 2014, Gen 3 will be arriving soon, and I can safely say its better than ever.

Gorilla Genealogy

The original Gorilla was constructed of a durable 210 denier PU-coated nylon ripstop fabric, had mesh outside pockets, a removable contoured one-piece aluminum stay, two webbing compression straps on each side, and stuffable 4-inch wide shoulder straps and hipbelt. The weight was 24.2 ounces.

In Gen 2 the Gorilla was constructed of Gossamer Gear’s 140 denier Dyneema Gridstop fabric, had fabric side pockets and a mesh front pocket, and retained the wide shoulder straps and hipbelt but without the option to stuff them with clothing. The side compression straps were dropped in favor of an external shock cord compression system. Pack weight increased to 26 ounces.

Now Gossamer Gear will soon be introducing Gen 3 of the Gorilla; what are the changes and how much do they affect pack weight?

The Gen 3 2014 Gossamer Gear Gorilla – What’s New?

The main changes are as follows:
  • The Gorilla is now constructed of Robic fabrics (see below for a description); the previous 140 denier Dyneema Gridstop exclusive to Gossamer Gear will be phased out.
  • The side compression straps are back (hooray!!), two on each side.
  • 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. (Identical and interchangeable with the Mariposa)
  • 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 previous cord/buckle to hold down the top cap.
  • Cord loops are added to zipper pulls on the hipbelt pockets and top cap pocket.

As you can see, the changes are basically the same as the updates to the Mariposa pack. The main difference from the Mariposa (besides volume) is the Gorilla has side compression straps and only one pocket on each side (versus the Mariposa’s one tall pocket on the left and two pockets on the right). The weight of the pre-production Gen 3 Gorilla is 28.3 ounces (size Medium) by my scale.

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 Gorilla

The backpanel view shows the Gorilla’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 are too wide for some people. The hipbelt is now 4.5 inches wide and ½-inch thick and is interchangeable with the Mariposa. It replaces 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 (gold) to snug down the top cap and new mesh on the front pocket.

The side view shows the pack’s side compression straps; welcome back! Side pockets are durable Robic fabric.

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. Note that the removable Thinlight pad supplied for the pack’s backpanel overlaps the hipbelt, providing extra lumbar padding.

Close up view of the new narrower/thicker shoulder straps.

Close-up of the new spacer mesh on the inside of the hipbelt, and shoulder straps.

The hipbelt pockets remain the same size and have a cord loop on the zipper pull to make them easier to open.

First Impressions

Based on my experience with previous generations of the Gorilla, and my testing of Gen 3 so far, following are my initial impressions:
  • After researching Robic fabric I am very impressed by its claimed strength, durability, and lower cost. It’s very easy to understand why Gossamer Gear made the switch. However, this is a new fabric to outdoor gear and its suitability needs to be tested under field conditions.
  • I am delighted to see the return of real webbing side compression straps.
  • Refinement. I like all the upgrades; the Gorilla just keeps getting better!
  • Pack weight continues to creep upward, another 2.3 ounces by my measurement, but that could change in the production pack.
  • Frame. Since the Gorilla is a medium size backpack, Gossamer Gear’s removable stay system is probably sufficient for weight transfer and carry comfort. Even with pack weights down to 15 pounds, my research has found that the removable stay effectively maintains pack torso length, transfers weight well without a closed cell foam pad, and helps the pack conform to the user’s back. The standard contour of the stay fits many users, and can easily be bent more or less to tailor it to the contours of a user’s back. Simply pull the stay out of the pack and bend it on the edge of a kitchen counter.


The Ideal Lightweight Backpack?

If your base pack weight is in the 8 to 12 pound range, with the volume that normally goes with that weight, the Gorilla is arguably the ideal pack for you. There several good packs out there in this size range (46 liters) that will comfortably carry the load, but the Gorilla is the lightest one I know of and has the best utility.


  1. Good review, hope the fabric turns out well in actual use.

    I think a very comparable pack is the HMG Windrider 2400.

    49 liters (with pockets), 28.2 ounces , easily capable of carrying over 30 pounds comfortably - I've carried 33, HMG says 40 pounds. People either love or hate the hybrid cuben fiber material, but HMG has been using that for several years now.

  2. My HMG Porter has abrasion marks from items rubbing the material and damaging it. Holes from other items puncturing it and that worn look - that compared to my Mariposa which is looking as new, yet has done about the same amount of miles tells me the hybrid cuben fiber material is not up to the task.

    Looking forward to seeing the new Gorilla Will and considering its my go-to 3 season pack I'm really excited about getting one.

  3. What are the weights of these robic fabrics (oz/yd^2)?
    Is it possible to buy them for MYOG yet?

  4. I don't have that information; anyone care to contribute?

  5. Did they make any changes to the removable stay? Looking at the side view photo, it appears to have a much more dramatic curve to it. Or did you bend it yourself? Those side compression straps are certainly an improvement, glad to see them included.

    1. No changes to the internal stay, I didn't alter the one in my test pack but you can bend it more or less to fit your back. The bendable stay is a big plus because it retains the shape of the backpanel that you want, and keeps that curvature no matter how much volume you have in the pack. A lot of folks use an inflatable sleeping pad nowadays, so no closed cell foam pad to create a virtual frame to transfer weight. The bendable contoured stay does that for you while giving you a custom pack fit at the same time.

  6. Hmm first impression is that the Gen 3 is a lot uglier than the Gen 2. Though the Gen 2 is a beautiful pack, wish the Gen 3 had the same look. That being said I'll keep my Gen 2 and it's 2+oz savings.

  7. I enjoyed your review of the gorilla. It appeals to me because of it's excellent harness system and webbing compression system. In your opinion would you expect the gorilla to handle 14 lbs of food plus 8-9 lb base weight? The awkward side pockets and lack of compression ability make the mariposa less appealing to me. Is there any way to get my hands on one to see how it fits before purchasing? I live in Maine. Thanks for your help

  8. Will...great review. I'm trying to reconcile the volume of the pack. The GG website states 38.6L for the Gorilla, while you indicate 46L. Honestly, 46L makes more sense to me when you consider that an HMG Windrider 2400 is 50L and a ULA OHM 2.0 is 63L and they seem like comparably sized packs.

  9. Jeff. I just purchased a gorilla and it is one superbly designed pack! I think the discrepancy comes from the extension collar not being factored I on the GG site.

  10. Thanks, John. Do you feel like the extension collar on the Gorilla is usable space? In other words, any issues with the functionality of the top flap if the volume in the extension collar needed to be used? Would seem strange if GG decided to show a lower pack volume if the ext collar space was indeed usable.

  11. Jeff. I see no problem using at least half of the extension collar volume. Per GG site: 1750 cu to extension seam 2354 total. The extension collar is 11x 6x 9 in = 594 cu. so perhaps the outside pockets aren't included in total. At home i loaded the pack with extension collar half full with No problem securing too lid.