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Gossamer Gear G4-20 Backpack Review

Gossamer Gear has just released a new minimalist, frameless backpack called the G4-20, a stronger modernized version of the G4, which was designed 20 years ago for the ultralight pioneer and founder of Gossamer Gear, Glen Van Peski.

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The G4-20 backpack has been designed for ultralight backpackers by ultralight backpackers. With pockets in all the right places, durability and practicality in mind, it’s obvious the creators of the G4-20 have spent a lot of time on the trail.

Like all frameless backpacks, the G4-20 has limitations on how much weight it can comfortably carry, so it’s best for backpackers who are dedicated to keeping their base weight under 10 lbs. That said, this pack is a simple, comfortable, and a great option for fast and light trips with dialed-in ultralight gear.

We’ve loved Gossamer Gear backpacks for a long time. The Gorilla 40 is one of our all-time favorite ultralight backpacks and the Mariposa is one of GG’s most popular packs, with a bit more capacity.

For more backpack recommendations, check out our 10 Best Lightweight Backpacks Guide.

Quick Specs

Gossamer Gear G4-20 Backpack

Price: $180

Weight (medium): 1 lb. 8 oz.

Volume (medium): 42L

Max Weight Rec.: 25 lbs.

Sizes Available: S, M, L (we tested S & L)

Colors: Grey & Electric Blue


  • Ultralight
  • Functional
  • Excellent value
  • Hydrophobic zippers
  • Comfortable
  • Hip belt pockets
  • Large front mesh pocket
  • Two large side pockets
  • Removable sit-pad
  • Removable straps


  • Frameless
  • Asymmetrical side pockets
  • Merely water-resistant
  • Mesh hip pocket less durable/functional
  • Non-breathable back pad



If you’re looking to hike more with less burden on your body, picking up an ultralight backpack is a good way to go. Your backpack will be one of the heaviest items you’ll carry, so it’s important to keep pack weight to a manageable size. The G4-20 weighs just 1 lb. 8 oz. (medium), which is amazingly light, less than a third of what a traditional backpack weighs.


The G4-20 is a well-rounded backpack with a simple, but functional design. It’s super lightweight, but doesn’t sacrifice durability to achieve that goal. The features of the G4-20 are thoughtfully engineered to make it easy to use on the go and the structure, straps, zippers, and pockets work well for their intended purposes.


The water-resistant TPU zipper tape used on the pockets of the G4-20 function smoothly and are easy to open and close with one hand. The pockets aren’t completely waterproof, but the tightly-sealing zippers do add a lot of water resistance and look great.


The shoulder straps and hip belt of the G4-20 are well-padded and fitted with mesh fabric on the underside that’s soft against the skin. As long as the load weight is kept to a minimum and this frameless backpack is carefully packed, the G4-20’s back pad is adequately supportive and comfortable to wear for hours at a time.


The G4-20 features a fixed hip belt with 2 different pockets. A zippered pocket on one side can accommodate a large cell phone with a case, and a stretchy mesh top-loader pocket on the other side keeps small items like chapstick, a snack bar, or compass close at hand.

Option 1 – clip buckles together in center


A generous elastic mesh pocket on the front of the G4-20 makes storing a jacket or anything you want to grab or stash throughout the day convenient and accessible. It’s also a great place to store wet gear, since the pocket is breathable and will allow airflow to circulate and continue the drying process while you hike.

Option 2 – clip buckles to side straps


The G4-20 has large pockets on each side to store water bottles. We prefer to use 1L Smartwater bottles since they’re lightweight and the shape fits nicely in pockets like those of the G4-20. The pockets are asymmetrical, one being shorter and easier to grab a water bottle out of. The other side pocket is taller and provides more secure for items like tent poles.


The molded foam back support pad of the G4-20 is easily removable and can be used as a sit pad, which saves you a bit of weight and bulk (we usually carry Therm-a-Rest Z-Seats with other backpacks). A minimalist sit pad keeps your behind warmer, dryer, cleaner, and more comfortable wherever you sit in the backcountry. This latest rendition of the back pad is easier to put in and take out and has ventilation holes for airflow.

The G4-20 has asymmetrical side pockets: one tall pocket (to stow tent poles) and another low side pocket.


The G4-20 has top and side straps that can easily be added or subtracted with loops and toggles. It’s common for ultralight backpackers to cut off straps they don’t use, but the toggle feature on the G4-20 allows you to keep your options open. The G4-20 also has adjustable shock cords on the sides to secure items in the side pockets or tighten the pack when it’s not completely full.

A close- up of the low side water bottle pocket


The G4-20 is a top-loading backpack with one large main compartment. The roll-top closure makes it easy to load and unload the backpack and can extend the capacity if necessary.The two options for closing the G4-20 are to roll the top down and clip the buckles to 2 side straps or to roll the top and clip it together in the center with a single buckle like a dry bag.

Mesh Hip pocket on one side less functional and durable.


The 42L capacity of the G4-20 is about right for a minimalist, frameless pack where you’ll need to keep your base weight around 10 lbs. For those who mostly use ultralight gear and practice minimalism, the G4-20 will have plenty of space for everything you need, but not too much space so that it’s awkwardly cavernous and frumpy when not filled to the gills.

other Mesh pocket is more traditional with zipper closure.



A lot of what sets the G4-20 apart from other backpacks is how ridiculously light it is. One of the main ways GG saved weight on the G4-20 was by making it frameless. That means it doesn’t have a framesheet or metal stays to give the backpack structure. If you’re a seasoned ultralight backpacker with a minimal base weight, a frameless pack like this could be an excellent choice. But if you try to pack too much heavy gear into any frameless backpack, it will quickly become uncomfortable. Frameless packs have lower weight capacities, don’t transfer weight to the hips as well, and have to be packed with more care to be comfortable against the back.


While the taller side pocket might come in handy for some backpackers who like to stow tent poles (or other long items) on the outside of the pack, we prefer the low side pocket for accessibility to water bottles. We’d find it more useful if the G4-20 had 2 identical low pockets instead of asymmetrical, but that’s our personal preference.


Very few backpacks are fully waterproof, but it would be awesome if they were! The G4-20 is made of a water resistant fabric and the roll-top closure helps it perform well in wet weather, but it should still be lined with a pack liner or trash compactor bag to keep your gear safe and dry in wet conditions.


The idea of convenience is nice, but the usefulness of the top-loading mesh pocket on the hip belt is more limited than a second zippered pocket would be. We prefer the larger capacity and security of the zippered pocket on the other side and would prefer 2 of them. There are attachment points for shoulder strap pockets though, so you can add extra storage to the G4-20 if you need it, say for a cell phone or point and shoot camera.


Though the molded back support pad has ventilation holes for airflow, we found it to be feel a bit hot and sweaty since it’s non-absorbent. The upside is that it dries quickly, so you won’t have to put on a wet pack after breaks. If you really want to improve breathability, you can upgrade to GG’s Air Flow SitLight Camp Seat. Order in the same size as your backpack.

Bottom Line

The Gossamer Gear G4-20 won’t be the right backpack for everyone, but experienced minimalists in need of a comfortable and highly functional frameless backpack should definitely take a close look at the G4-20. We’re big fans of its comfort, durability, functionality, and value.

If you think the G4-20 might be a bit minimal for you, Gossamer Gear has a lot of great backpack options and many have more supportive frames for carrying heavier loads. Check out Gossamer Gear’s ‘Which Backpack is Right For You?’ Guide for an overview of their most popular products. And for more CleverHiker backpack recommendations, check out our 10 Best Lightweight Backpacks Guide.