If you’re looking to take your lightweight backpacking game to the next level, you may be considering a personal graduation from the Gossamer Gear Mariposa 60 Backpack to our Kumo 36 Superlight Backpack. Or, maybe you’re looking to up your speed on trail and are eyeing our Fast Kumo 36 Fastpack. In either case, you might be wondering: what’s the difference between the two Kumo packs anyway? 

Below, we’ll break down what differentiates the Kumo from the Fast Kumo to help you choose which is the best lightweight backpack for you. We also turned to a couple of our brand ambassadors who have made the switch from the Kumo 36 Superlight Backpack to the Fast Kumo 36 Fastpack for their insights. As power users of both packs, they have lots of on-the-ground experience to help inform your decision.

Meet the Brand Ambassador Experts



Lauren “Sparkle” Veloz (she/her), or Lolo, is a Denver-based long-distance backpacker who hiked the Appalachian Trail in about 112 days as a “section” of the Eastern Continental Trail. She was the first known woman to hike this route and was on a time crunch, so her main goal was to move as fast as she could with the least amount of weight on her back. Hence, the Fast Pack became a quick friend.



Riley “Waldo” Ormiston (they/she) is from southern California and has completed multiple Pacific Crest Trail LASHs (Long Ass Section Hikes, if you’re unfamiliar with the term!), the John Muir Trail, the Lowest-to-Highest Route (which runs from Death Valley at 280 ft below sea level to Mt. Whitney at 14,495 ft), and more. They shifted to the Fast Kumo on the PCT as their gear needs began to change.

What Features Differ on the Kumo vs. Fast Kumo?

The Kumo and Fast Kumo share a lot of the same DNA. They’re both 36-liter packs. They’re both constructed with custom 70D Robic nylon on the top and custom 100D Robic nylon on the boot. They both have the same over-the-top closure, removable SitLight pad, detachable fastbelt, and angled stretch-mesh pocket on the front.

Both packs have my essential features intact: a truly cavernous mesh pocket on the back, hip pockets that can hold my entire day’s worth of snacks, and a thoughtfully designed internal volume that perfectly fits my Thermarest, sleeping bag, and BV450 horizontally. – Riley

The tough, frameless Kumo pack design that has been beloved by thru-hikers for years is present in both models. It’s from this solid foundation that the Fast Kumo made a few pivots to support additional use cases.


One of the standout features of the Fast Kumo is its vest-like harness, inspired by classic running vest styles. The shoulder straps are cut to hug the chest and designed to hold many small items within reach. They’re made from layers of perforated foam and mesh to increase breathability and reduce weight. The harness also includes two sternum straps to reduce bounce and ensure a snug fit. 

The Kumo has shoulder straps that are more standard for backpacking. They’re ergonomic, allowing for a secure but flexible fit. The harness leverages one sternum strap, giving the pack a carry feeling more aligned with our other backpacking packs like the Mariposa 60.


The Fast Kumo is designed to be worn higher and tighter for less jiggle during fast movement, whereas the Kumo mirrors what you might expect from the Mariposa 60. The Kumo sits a little lower with a bit more flexibility for standard hiking trips.

The Fast Kumo sits a little higher and ‘hugs’ me closer than the regular Kumo, so it feels more secure for when I’m bouncing around trying to move fast through the mud, roots, and rocks on the AT versus the groomed trails that I’ve used the regular Kumo on. – Lolo


The Fast Kumo was designed for hikers, fastpackers, and trail runners looking to cover greater distances more quickly. This means they’re less likely to want to take breaks for snacks, hydration, or accessing on-the-go gear. To support this, the Fast Kumo has additional easy-access pockets when compared to the Kumo. 

There are six elastic-secured stash pockets of varying sizes on the Fast Kumo’s shoulder straps that can hold everything from electrolyte tablets to a full water bottle. One is accessible from the bottom as well, making it an easy trash-stash while keeping pace. There’s also an additional zippered pocket on one of the shoulder straps for items you may want to keep more secure, like a phone. Additionally, the side pockets on the Fast Kumo can be accessed from the top or side for quick, on-the-go grabbing and stashing.

The Kumo has a more standard, streamlined storage and access system. It has two water-bottle-sized pockets on each side, as well as a stretch mesh pocket with elastic at the top on each shoulder strap.

If you’re curious how utilizing the quick-access pockets would look like on the Fast Kumo, check out our Instagram video highlighting these features.


Ok, so this isn’t really a feature, per se, but trail fashion is a consideration! The Fast Kumo is offered in gray and black with orange accents, whereas the Kumo comes in gray and black with red accents. If you were lucky, you may have also snagged the Kumo in our limited edition Vaporwave colorway—a fun mix of purple, teal, black, and peach.

Different Use Cases for the Kumo vs. Fast Kumo

The Kumo and Fast Kumo both perform well on a variety of outings, but depending on what conditions you’re expecting more frequently, you may prefer one over the other.

The Kumo is great for when you might need to carry a little extra weight, such as in drier environments with fewer opportunities for water fill-ups. If you’re doing backpacking trips or weekend warrior routes on fairly well-maintained trails, it’s a great option. The Kumo is a perfect pack for when you want to take your ultralight game to the next level, but still want the classic feel of a backpacking pack.

If you jog, walk any faster than 4.5mph, or do any off-trail Class II+ travel, I think the more balanced carry of the Fast Kumo is well worth it. It feels much tighter on the body and more stable, less bounce—really secure for more bouldery Class III stuff. If you have shoulder issues like me, having front-loaded water bottles can also be much easier to grab while walking. But… I like the red accents of the original Kumo better! There’s also something to be said for the simplicity of the OG pocket scheme, which can be pleasingly less complex if you don’t want to think about optimizing where you’re putting all your stuff.  – Riley

The Fast Kumo is great for scenarios where you want to move fast, maybe even do some trail running. Its intended use case was for fastpacking, but it comes in handy for any type of trek where you might need a more secure fit. If you’re doing some climbing or off-trailing, the Fast Kumo is a great option. It’s also good for anytime you need quicker access to food, water, or other supplies.

The AT has bountiful water sources and great accessibility to towns and shelters making the Fast Kumo the perfect size to dash between resupplies with shorter water carries.  – Lolo

True Life: I Made the Switch to the Fast Kumo

So, what made Lolo and Riley switch from the Kumo to the Fast Kumo? For Lolo, it came down to convenience and comfort.

I struggle remembering to eat and drink unless it’s readily available and convenient for me to grab; so, the ability to keep snacks, securely stash trash, and hold a 750 ml water bottle AND my cold soaking container (peanut butter jar) in the front straps is a huge reason I love the Fast Kumo! The straps are so soft and adjustable while also fitting my figure comfortably—unlike a lot of running vests that tend to squish me in all the wrong places. – Lolo

Riley’s switch came after many miles and adventures with the Kumo where they started to realize they needed a pack suited for faster travel through uneven terrain.

The Kumo has been my favorite pack for years—it’s been my go-to for Sierra trips, Lowest-to-Highest, and all manner of trips in the Channel Islands, really anything with less than a week of food weight. It was the perfect size for me for the PCT—a 10-pound base weight and 20-pound comfort limit leaves you all kinds of room for the relatively short food carries of the trail. 

But, the PCT in 2023 had some unique gear demands. Leaving Kennedy Meadows in June with full shoulder-season gear and a week of food, my Kumo weighed in at 34 pounds (don’t tell the Gossamer Gear design team!). I had to stash my tent on the outside, which really took away points for aesthetics, turning a little orb-like. The pack handled it like a champ—but I don’t necessarily recommend doing this.

My Kumo, in particular, has been subject to all kinds of nonsense it wasn’t designed for: hauling 20 pounds of water through Death Valley, bushwhacking through heavy undergrowth, squeezing through tight slot canyons, etc. By the time I made it to Oregon, my sweet Kumo with well over 2,000 cumulative miles was getting a little creaky in the shoulder straps, especially when I jogged. It was time for something… faster. – Riley

4 Considerations for Using the Kumo or Fast Kumo Backpacks

If you’re trying to decide between the Kumo or the Fast Kumo, here are a few considerations that Lolo and Riley recommended.

1. Give Yourself Time to Adjust

The Fast Kumo has a different harness than the Kumo or other backpacks you may be used to carrying. Allow an adjustment period before taking it on a multi-day adventure to let your shoulders and chest get used to the feeling.

My primary advice to someone switching from the standard to the Fast Kumo is this: go easy on the weight for a few days until your shoulders adjust. I found the standard Kumo’s shoulder straps to be slightly wider and/or cushier, which distributed the weight better. I love overloading my Kumo, but I’d take the 25 lb max load of the Fast Kumo more seriously, at least at first. – Riley

2. Pay Attention to Your Load

The Fast Kumo is about going fast and light. While you may have a habit of overloading other packs, try to use your Fast Kumo as an opportunity to really pare down your kit. It can also be a great go-to for shorter trips.

The Fast Kumo is truly most comfortable under 25 lbs, so I’d choose this pack for trails with resupplies around 3 to 4 days max, while I’ve seen the Kumo loaded with up to 6 days and still carry well! The zipper pocket on the straps and extra D rings on the Fast Kumo are features I much prefer as well. – Lolo

3. Think About Your Storage

The number of pockets on the Kumo and Fast Kumo vary. Consider how you like to access your gear and whether front-loading some key items on the shoulder straps appeals to you.

Using the Fast Kumo’s shoulder strap pockets for water bottles (500 ml and 700 ml Smartwater fit perfectly) gives much easier access to them on trail, and makes for better weight distribution. This is noticeable if you’re walking, but extra important if you’re jogging down a hill. However, this also means whatever goodies you were keeping there before may need a new home. While my phone fit perfectly in the zipper pocket on the left shoulder strap, my little camera never found a home that was equally secure and accessible. It ended up in my shorts pocket in the morning, then in one of the hip belt pockets after I’d eaten some snacks. – Riley

4. Choose Your Harness Preference

The Fast Kumo has a double sternum strap, whereas the Kumo has a single sternum strap. Think about whether you want a snugger fit with the dual straps or if you prefer the extra breathing room of a classic one-strap harness.

The double chest strap is great once you get it dialed, but required some trial and error to get there, for me. The standard Kumo’s single, stretchier strap is slightly more comfortable and less restrictive for easy walking, but I notice it can ride up the rails if I jog a lot. The Fast Kumo’s double straps clip into slots, so they can’t accidentally shift. They’re more customizable to your body and comfort, though I had minor discomfort when breathing really heavily during the Dump Truck Challenge in Washington. – Riley

Select the Kumo or Fast Kumo Backpacks for Quick, Light Adventure

The Kumo and Fast Kumo share a lot of the same great features, but also differ in some key ways. Consider your hiking, backpacking, fastpacking, or trail running goals when picking the best pack for you. And we hope that Lolo and Riley’s insights can help you decide whether a switch to the Fast Kumo might be right for you!

Whether Kumo, Fast Kumo, or a little bit of both, we’d love to share in the adventure with you! Make sure to share the fun with us by tagging Gossamer Gear on social media (@gossamergear) and using the hashtag #takelessdomore.

Hungry for more backpacking gear and planning knowledge? Check out some of our other articles on the Light Feet blog:

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March 22, 2024 — Korrin Bishop