The Durston Gear Kakwa 40 Backpack is an ultralight, internal frame pack that weighs well under 2 pounds with a total volume of 55L including 40 liters in its main compartment plus 15 liters of additional external storage. It provides excellent weight transfer to the hips with moderate loads and is one of the least expensive packs on the market made with abrasion-resistant Challenge Ultra 200 fabric. SectionHiker was very impressed with Durston’s X-Mid 1P (v2) and we think there are a lot of users who will find the Kakwa to be an excellent pack for their needs. We also suggest a couple of minor improvements to broaden the pack’s applicability.
Specs at a Glance
These specs are for a size medium (16.5”-19.5”/ 42-50 cm torso) pack, which we tested. The Kakwa 40 also comes in small (14.5″–17.5″ / 37–45 cm torso) and large (19″–22″/ 46–55 cm torso) sizes.
- Weight (manufacturer): 27.8 ounces (1.75 pounds)/790 grams
- Weight (tested) 26.88 ounces (1.68 pounds)/762 grams
- Gender: Unisex, with S-shaped shoulder straps
- Pockets: 7: 2 asymmetrical side pockets (1 with extra “QuickPocket” zip pocket), 2 hipbelt pockets, 2 shoulder strap pockets, and a front mesh pocket.
- Color: Gray
- Type: Internal Frame (8 mm hollow aluminum inverted U-shaped tubing)
- Hydration compatible: Yes
- Seam-taped: No
- Bear Canister Compatibility: BV500 fits vertically, or strapped to the top
- Internal Volume: 41L (2502 cubic inches)
- External Volume: 15L (915 cubic inches)
- Top circumference: 36”/91 cm
- Bottom circumference: 31”/78 cm
- Unrolled height (M): 33”/84 cm
- Materials: 3.5 oz/ sq. yd. 200D Challenge Ultra (Main Body+Side and Hipbelt Pockets), Stretch fine-pore mesh (Shoulder Strap Pockets), Heavy-duty polyester knit low-stretch mesh (Front Pocket), YKK AquaGuard Zippers
- Maximum Recommended Load (manufacturer): 45 lbs
- For full specs, see the product page at Kaviso.com (the distributor)
Backpack Storage and Organization
The Kakwa 40 is a clean-looking pack with a number of classic ultralight pack features as well as some distinctive design elements. Developed by Durston Gear owner Dan Durston, a backpacker, and adventurer with an impressive hiking resume, a lot of consideration has gone into features that allow you to access the essentials you need during the day without having to stop and remove the pack.
The main pack bag is a single compartment and holds approximately 40 liters, depending on size (small is 38 liters, medium is 41 liters, large is 44 liters). While many large retail backpack manufacturers include all the closed storage in their volume calculations, it is more common in the cottage industry (and is the case with Durston’s Kakwa) to name the pack based on the storage capacity of the main bag only. The main bag closes with quick-release buckles that attach to themselves, in the style of a dry bag. There are no additional buckles and webbing on the sides to which you can connect the roll top.
On the outside of the pack, there are asymmetrical side pockets, zippered hipbelt pockets, a pleated mesh pocket on the pack’s front, and two stretchy shoulder strap pockets. According to the manufacturer, the Kakwa 40 has an additional 15 liters of storage between these external pockets.
Let’s take a closer look at each of these features.
Shoulder strap pockets
I really like the shoulder pockets on the Kakwa 40. They are made of a stretchy, fine-pored Lycra-like mesh with a cordlock and shock cord closure on top. They are a very convenient and accessible way to carry bear spray, phone/camera, satellite messenger, sunglasses, or 16-20 oz water bottles (one-liter bottles are too tall or wide for these pockets). The only problem is deciding which two of these things you want to carry here! The top elastic cinches closed with one hand for security while you’re scrambling. Well done.
The side pockets are asymmetrical, with the right-hand side pocket cut at a diagonal to facilitate easy water bottle access, and the left-hand pocket taller and cut straight across. Both pockets are 3-dimensional, with a half-circle of fabric sewn as the bottom panel of the pocket. I prefer 3-D pockets like these to pleated pockets, because I prioritize ease of access and more capacity over the ability to fold flat when not in use.
Both side pockets and the front mesh pocket have non-adjustable and non-replaceable elastic that is captured inside a channel of Ultra fabric. Dan Durston says that capturing the elastic in this way prevents damage and wear, allowing for a longer lifespan than pockets with elastic binding. My experience agrees with this: although my favorite pockets have user-replaceable cord, I’ve seen elastic-bound pockets go limp in a couple of years, while my old Lowe Alpine pack with captured elastic pockets still had stretch after more than a decade.
The capturing of the elastic means that pocket tension is permanently set; the user can’t tighten or loosen the pockets depending on their contents.
I had no problem removing and replacing a single water bottle from this pocket– even though it is on my non-dominant hand side. However, when I carried two bottles in this pocket, the fit was tight and I had to ask for help from my hiking partner to access and replace a bottle.
The taller left-hand pocket is ideal for larger items like a tent, Tenkara rod, tent poles, or a collapsible water carrier like a Platypus that would flop over in a lower-cut pocket. This pocket is uniquely constructed with a double layer and a vertical zip that is accessible while wearing the pack–called the QuickPocket. The inner and outer pocket play a zero-sum game with space, so the less you put in the inner pocket, the more volume is available for the QuickPocket, and vice versa. I found that, when I had a water bottle in the inner pocket, my crushable boonie-style hat could fit in the QuickPocket, but my rigid-brimmed cap with a sun cape could not.
The best use I found for this pocket was stashing and accessing a map on the go. I could slide it in horizontally and tuck the top of the map behind the little strip of fabric on the side of the zipper closest to my back, and then zip it closed for security, all while wearing the pack. This was much more convenient than using a map holder clipped to my shoulder straps, or keeping the map in the front mesh pocket and having to take the pack off or ask a buddy to get it every time I wanted to check it.
While many packs raise their side pockets up an inch or two from the bottom of the pack to protect them from abrasion, the pockets on the Kakwa are flush with the bottom of the pack and are made from the same durable material as the bottom of the pack–Challenge Ultra 200. This design feature also helps with the accessibility of your water bottle in the diagonal-cut pocket, because it allows the opening to be lower.
I was surprised to see that there are no drain holes on the side pockets. More on this later.
Mesh front pocket
The mesh pocket on the front is a heavy-duty polyester low-stretch mesh that is pleated at the bottom. This means it can expand to hold a fuel canister, water filter, wet tarp, or rain jacket but is not droopy when empty. As described above, the top elastic for the pocket is captured in a sleeve of Ultra fabric, so it’s protected but its tension cannot be adjusted.
Hip belt pockets
The hipbelt pockets are 6” long x 3” tall x 1.5”-2” wide (2” at the base tapering up to 1.5” at the zipper) and close with a YKK AquaGuard water-resistant zipper running over the top. The zippers open from front to back (i.e. you open them by pulling the zip towards you) and can be easily opened and closed with one hand. I really appreciate this easy access because I’ve used a number of hipbelt pockets on other packs that require two hands to open. I mostly use these pockets for a headlamp, head-net, and snacks.
There is a hydration port on the right side of the pack, but no hanging hardware (e.g. sleeve, webbing loops, toggles, or mitten hooks) inside. I’m assuming the design thinking behind this is to pack all your gear in a waterproof liner and set the full bladder horizontally on top. Absent a dedicated external hydration sleeve, this technique provides the easiest access to your hydration bladder for refilling and puts the least amount of pressure on it. My hydration bladder is from 1997 and the tube is only pressure-fit to the bladder, so it can pop off (I should probably superglue it). Modern bladders use quick-release hardware that is less likely to pop off and cause a flood.
Backpack Frame and Suspension
The frame and suspension of the Kakwa 40 pack include the following elements: a U-shaped internal frame tube, a foam pad, a sewn-on hipbelt with a forward-pull adjustment, shoulder straps on a yoke, and load lifters.
The frame is a hollow aluminum tube bent in an inverted U shape with contours to follow the small of the back. It cannot be bent further by the user but should work as-is for most. A thin piece of foam provides some protection for your back from hard-edged items you may pack, and, while both can be removed by the user, we don’t recommend it. Removing the frame and pad saves only four ounces and loses the great weight transfer of this design.
Some early purchasers of the Kakwa didn’t realize that there were four total webbing channels that the frame needs to slide into. So when they replaced the frame after removing it, they inserted the frame into the top two channels and missed the bottom two, and thus abraded small holes where the frame ends rubbed up against the fabric. It’s understandable that this happened because the frame channels are hidden behind a ripstop fabric pocket that does double duty holding the frame under tension as well as holding the foam pad. Fortunately, Durston has been covering these packs under warranty until a warning message can be added to the pocket.
The thin foam is similar to what’s used in many sewn-in back panels (I’ve taken apart a bunch of backpacks and seen it) but it is more like a plastic packing foam than your standard sleeping pad foam. The pocket that houses both frame and pad is a very tight fit, but this tight fit is important for locking the frame in place with no wiggliness.
The shoulder straps are S-shaped, which is better for people with more developed chests than J-shaped straps because they curve around the chest instead of running directly over it and pressing against it. There is a bar-tacked daisy chain running down the center of each strap, which continues behind the built-in stretch pockets, which are attached at the top and bottom only. The sternum strap hooks to the daisy chains behind the pockets. Because of the daisy chains, you could add shoulder strap pockets over the stretch pockets if you prefer a different style of shoulder pockets (maybe with a zipper, or with padding for a camera) to the built-in stretchy ones. Or, if the pockets ever rip, you could cut them off and have full daisy chains to rig up their replacement.
Instead of the shoulder straps being sewn on individually, they are joined together in a yoke. This means the load is spread across a much longer seam, which can help prevent the shoulder straps from ripping out.
The load lifters are attached to a fixed point on the shoulder straps, and to the back panel 3 inches above the seam the shoulder straps are sewn into. They share a seam with the top flap of the frame pocket. Sharing this seam provides a strong connection to the top of the frame, which is held in place by the top of the frame pocket. Tightening the load lifters had a significant effect on moving the top of the frame closer to my back for more stability.
The hipbelt is a sewn-on, wing-style hipbelt with 3D mesh against the user. Each wing is 10” long, and they are sewn onto the pack 6”-6.5” apart (the width tapers up a half inch from bottom to top). From end-to-end, the hipbelt wings measure 26”-26.5”. The webbing makes the hipbelt adjustable from 28”-42”, but folks on the larger end of that spectrum may find that the hipbelt wings don’t wrap far enough around the front of their hipbone to provide optimum weight transfer. I suggest you use a tape measure on your own hips and use the specs we give to see where the belt would end for you. Larger hipbelt (longer wing) sizes may be introduced later by Durston Gear.
Looking inside the hipbelt pockets, I can see the texture of the hipbelt foam, which is not flat, but subtly contoured with small hills and valleys, presumably for a more flexible wrap. The hipbelt has a forward-pull adjustment to tighten the belt. The webbing is sewn onto either wing in a sideways V shape to allow for conical tightening (i.e. wider at the bottom, narrower at the top) but each side adjusts with a single pull and there is a single center buckle to close.
Max Recommended Load
The ends of the frame terminate right where the hipbelt attaches to the pack, so the load transfer to the hips is excellent. The carry is very good and comfortable with moderate loads.
At 20 pounds, I felt as good as I do when carrying 10 pounds or less in a frameless pack. Between 30 and 36 pounds, I was still impressed by the carry but noted that, on especially hot, sweaty days, I needed to really crank down on the hipbelt to prevent slippage down my back between the two hipbelt wings, where there is slippery Ultra fabric instead of 3D mesh. I tried the pack with 40 and 45 pound loads too, but for my small frame, I would prefer to switch to a load-hauling pack at those weights. The Kakwa’s sweet spot for me is 15 to 30 pounds, but your mileage may vary.
External Attachments and Compression
External attachments and compression on the Kakwa 40 are quite simple, consisting of a single tier of static cord and lineloc tensioner on either side of the pack, and a Y-shaped strap of webbing that goes over the top of the pack. There are also a few small loops of grosgrain through which additional attachment points can be rigged up.
There are two tiny grosgrain loops at the base of the front mesh pocket, and 4 grosgrain loops (2 per side) that the side compression cord attaches to, that have enough room to run an additional cord through. You could attach trekking poles or an ice ax by rigging up a loop of cord through one of the grosgrain loops at the base of the pocket and a loop of shock cord and a cordlock through one of the grosgrain loops at the top of the pocket where the side compression attaches. Or you could criss-cross shock cord through the four pieces of grosgrain around the pocket to create additional compression for items in the pocket or a place to stow wet gear outside of the pocket.
Side Compression Cord
The static cord is good for hanging socks to dry, or stabilizing long items in the pockets like tent poles or a fishing rod. It’s easily user-replaceable if it breaks or if you need a longer cord. It is limited in the amount of compression it provides and is not sufficient for strapping heavier items like snowshoes to the sides of the pack. The only way I can see to attach snowshoes is on top of the pack, under the Y strap.
A Y strap is often described as having two functions: providing compression from the top down, and strapping large items to the top of a pack. In my experience, rolling the top of a roll top pack is sufficient by itself for top compression, and you can clip the top together in a way where the clipped loop lies flat instead of sticking up and snagging on brush. The top of the Y strap attaches next to the load lifters, adjusts on one side with a ladder lock buckle, and is permanently attached to the other. The “leg” of the Y strap attaches at the top of the mesh pocket on the front, and connects to the “arms” of the Y with a quick release, adjustable buckle. That’s right–there are two points of adjustment on the length of the Y strap. This is helpful for maximizing the wrap of the two arms over whatever you’re strapping on, as two straps are better than one for security.
The Y strap can be used to carry snowshoes, a tent, a foam sleeping pad, or a bear canister, depending on your needs–but not all at the same time! It is a good idea, when strapping critical gear to your pack, to have some form of redundancy to keep it connected to you in case it slips out while you’re walking. In the case of a tent, you might use a mini carabiner to clip the stuffsack drawstring to the side compression cord.
If you are not using the Y strap to attach additional gear, you really need to have it clipped closed to keep its webbing out of the way, but this creates an additional step to getting into your pack.
Bear Canister Compatibility
Durston says a Bear Vault BV500 fits vertically inside the main compartment or can be strapped to the top. Many bear canister users like to keep a bear can out of the main compartment to free up space, but it’s perfectly acceptable to carry it inside if you don’t need all the space for your other gear. It would be helpful for Durston Gear to publish a chart of which other canisters on the market could fit inside, either horizontally or vertically.
I tried strapping both a Garcia canister and a Bear Vault BV500 to the top. Although I hadn’t completely filled the pack to capacity, I could just barely connect the strap over the top of a BV500 with the strap completely maxed out from both adjustment points. If I had a fuller pack, I wouldn’t have had enough strap length to close it. A Garcia canister fit better, allowing me to cinch the strap down a couple of inches. But extra strap length here would be most welcome.
The Y strap held both models of bear canister securely through dynamic movement, with a slight edge to the Bear Vault, whose multiple ridges allowed the Y strap to sit between them. If you decide to carry a bear canister on top, one way to minimize the top-heaviness of your pack is to keep your food in an odor-proof bag inside your pack and run the canister empty strapped to the top. Then you fill it when you get to camp.
I tend to cut off permanently-attached top straps to sew on hardware to make them removable, and will likely do the same thing here. That would allow me to remove it entirely when it’s not needed, making it quicker to access the main bag, and also to customize the length of webbing to whatever I might strap on top.
The Kakwa 40 uses Challenge Ultra 200 fabric throughout most of the pack. The only exceptions are the stretch mesh shoulder pockets, 3D mesh on the inside of the hipbelt and shoulder straps, non-stretch polyester mesh for the front pocket, and ripstop material for the internal frame pocket.
Ultra, a blend of 67% Ultra High Molecular Weight Polyethylene (branded versions of this fiber are known as Dyneema and Spectra) and 33% recycled polyester with a recycled waterproof film backing, has taken the backpacking world by storm among innovative cottage manufacturers but has yet to be adopted by slower-to-change mainstream companies whose gear is sold at retail shops. Its claim to fame is light weight with high water resistance and extremely high abrasion resistance in lab testing (the Taber test), while also being softer (to touch) and quieter than many laminate fabrics. It currently comes in 4 deniers (100, 200, 400, and 800), with higher numbers being increasingly durable but also increasingly heavy.
Ultra fabric’s fibers don’t absorb water, so the pack dries very fast when it gets wet, and it’s backed by a waterproof film for more water resistance. However, because of the complexity of the seams around the frame assembly, the Kakwa is not seam taped or seam sealed–the seam allowance is bound with grosgrain. This means it’s important to use a waterproof liner–a practice that’s a good idea with most any backpack that’s not a legit drybag–in the rain or when packrafting, to keep your gear dry.
However, a greater issue in terms of water resistance of the Kakwa 40 is the fact that the side pockets do not have drain holes. I like to test water resistance by bringing gear into the rain close to home (without using a liner) before taking it on a trip. After bringing it out in a torrential downpour, I noticed that the items in the bottom of my pack were damp, despite the fact that the roll top was tightly sealed. The higher items were packed in the backpack, the less wet they were. This was confusing to me. I looked into the side pockets and noticed the interiors were wet but not holding large amounts of water.
So a few days later I did a test where I poured a liter of water into one of the side pockets while the bag was empty. I saw that, since there are no pocket drain holes, the water seeped out through the seams. I noticed water dripping out of the seams of the pocket on the opposite side, even though I hadn’t put any water into that pocket. Looking into the body of the pack, I saw that water was entering the main bag through the seams, puddling at the bottom, and then seeping out through the pocket seams on the other side.
Obviously, this was an extreme test–pouring a liter of water into a pocket is a high-pressure scenario, and I always use a pack liner with all packs, regardless of how well-sealed it is. Also, there is some extra protection of the pockets in the way that the Kakwa’s built-in wide elastic tends to curve the top of the pocket over and around the gear, creating a partial “umbrella.” I had this pack out during two more downpours during my testing period where a small amount of water entered the main compartment, and I believe that water entry wouldn’t have been as much of an issue if there were drain holes in the side pockets that let the water out rapidly before it could seep through the seams. If you recreate in an arid environment this may be moot to you.
Comparable Ultra Backpacks
|Make / Model||Total Volume||Fabric||Weight|
|Durston Gear Kakwa 40||55L||Ultra 200||27.8 / 770g|
|Zpacks Arc Haul 50||50L||Ultra 200 & 100||20.4 oz / 577g|
|ULA UL24 Ohm||63L||Ultra 200 & 400||31.8 oz / 902g|
|LiteAF Ultra Curve 46||61L||Ultra 200||31 oz / 879g|
|Bonfus Framus 48||48L||Ultra 200||25.4 oz / 720g|
|Mountain Laurel Designs Exodus||55L||Ultra 200 & 400||18 oz / 510g|
|Volpi Outdoor Gear UL 40||45L||Ultra 200 & 100||14.8 oz / 420g|
|Superior Wilderness Designs Movement 50||50L||Ultra 200||23.8 oz / 675|
For me, the Durston Gear Kakwa 40 nicely fills a niche between my ultralight frameless pack and my enormous framed pack. It lets me carry loads that would be uncomfortable for me in a frameless pack but for which a heavy load hauler would be overkill. The low weight is impressive for a framed pack, especially considering that ours came in under spec! The pocketing is fantastic for accessing what you need during the day without stopping. The design, carry and features would be great even if a more conventional pack fabric was used, but if you’ve been curious about trying a pack made from Ultra fabric, the Kakwa 40 is one of the least expensive Ultra packs on the market today.
- Great load transfer at 20-30 pounds
- Clean, streamlined design without a lot of straps flapping around
- Hipbelt pockets that easily open and close with one hand
Unique QuickPocket is a perfect place to store and access a map on the go
Versatile, secure and easy to use shoulder strap pockets
Room for improvement
- Add drain holes to side pockets
- Make the over-the-top Y strap longer for bear canisters
Disclosure: Durston Gear donated a backpack for this review.