Id never seen a bear canister like the one before me at the REI Co-op Magnusson Lab in Seattle. The translucent orange container was sitting in a device that looked like a guillotine, and I watched as it pressed a steel bears tooth down into the plastic exterior. Two of REIs lab researchers stood quietly beside me, watching as the point of the steel tip pressed deeper into the canister.

　　The plastic held, deforming under the force without the tooth breaking through. Eventually, it punctured —but that was allegedly beyond the force a bear can generate with its jaws. The test was successful. REIs first-ever bear canister worked.

　　(Photo/Will Brendza) That wasnt what impressed me, though — lots of bear canisters work. What really stuck out about the REI Co-op Traverse Bear Canister was its modular capability.

　　This canister allows you to change its volume for longer or shorter trips or trips with different-sized groups. Its essentially two bear canisters in one. That seemed novel, and I was eager to get my paws on one and start testing it.

　　In short: The REI Co-op Traverse Modular Bear Canister can change sizes based on the amount of food you need on the trail. If youre traveling in bear country for longer, this canister can fit 686 cubic inches of food. If you dont need that much space, it can be downsized to 412 cubic inches. For backpackers who travel in bear country often, this bear-resistant canister is a versatile option — if a heavy one.

　　REI Co-op Traverse Modular Bear Canister Check Price at REI

　　(Photo/ REI Co-op) 8.0 How we rate products Specifications Best use: Backpacking Gear capacity (L): 11.25, 6.75 Gear capacity (cu. in.): 686 (large); 412 (small) Materials: Polycarbonate; carry bag: 100% recycled ripstop nylon Dimensions (large configuration): 9.1 x 13 Dimensions (small configuration): 9.1 x 8 Weight (large configuration, excluding carry bag): 3 lbs., 9.1 oz. Weight (small configuration, excluding carry bag): 2 lbs., 8 oz. Pros Versatile for different lengths of backpacking trips Certified bear-resistant Translucent so you can see inside Cons Heavy Opening it is challenging with cold fingers Will Brendza REI Co-op Traverse Modular Bear Canister First Look When REI announced its Traverse Modular Bear Canister, GearJunkie covered the story and promised a full review. For full disclosure, I didnt take this canister backpacking. I took it camping on the western slope of Colorado twice and used it as my food container.

　　The areas where I camped have black bears, but not brown or grizzly bears. It was in early April, too, so its possible some bears had not emerged from hibernation yet.

　　(Photo/Will Brendza) That said, I got familiar with this bear canister over a total of 4 nights and 5 days and had some takeaways that are worth sharing. As far as the bear-resistance claim goes, I trust the Inter Agency Grizzly Bear Committees (IGBC) certification. It is the gold standard of bear-resistance accreditation because it uses real bears to test products like the Traverse Modular Bear Canister, or coolers like those made by YETI and RTIC.

　　I was also in the REI Magnusson lab and witnessed the test described above. I have little doubt this bear canister would foil a bear from getting at whatever is stashed inside of it.

　　The question I wanted to answer during my testing was, how user-friendly is this unique modular design?

　　Locking Design

　　(Photo/Will Brendza) The design of the REI Traverse Modular Bear Canister is actually pretty simple. The lid and canister sections screw together and lock in place with spring-loaded metal buttons. There are three sections: The lid, the middle, and the bottom. The middle section adds 274 cubic inches of volume. The bottom section can nest into the middle section if you arent using it.

　　To unscrew the sections, press the button tab marked 1 to disengage the lock, and then turn it until the button is recessed in the canister body. Press the button tab marked 2 and the lid should unscrew completely. The REI video below shows a demonstration of how to unlock and unscrew the sections.

　　Play However, in my experience, unscrewing this canister isnt as easy as that video makes it look. You can probably unscrew it with one hand (as in the video), but I struggled to do that. Maybe Im part bear, but the size of the buttons, the slippery plastic, and the twisting action conspire to make the task decidedly difficult to accomplish.

　　The easiest way for me to do it was to hold the canister between my feet, press the buttons, and twist from the top. That gave me the right leverage and made it a lot easier to open it up or modify the size.

　　(Photo/Will Brendza) I also found that those metal buttons are hard and somewhat painful to press with cold fingers. Call me a wimp. But when I woke up to a light rain on a 32-degree morning, my cold, gloveless fingertips didnt like pressing those small metal nubs hard enough to unlock them.

　　If you have a key, a small stick, or other similar implement, you can use that to press the button in and save your fingertips some hassle.

　　Nesting

　　(Photo/Will Brendza) Longer trips might require the full capacity of the Traverse Modular Bear Canister — at first. But toward the end of the trip, you might have eaten a lot of your food. That sometimes means the bear canister takes up unused space in your pack.

　　(Photo/Will Brendza) But REI thought of this. Thats why the bottom section of its Traverse canister actually nests within the middle section. That way, as your food supply shrinks, you can shrink the container size as well, saving otherwise dead pack space.

　　Cost-Effective Capacity

　　(Photo/Will Brendza) Usually, people either use their oversized bear canister for all of their bear country backpacking, or they buy multiple bear canisters for different length trips. The benefit of the Traverse Modular Bear Canister is that you get two different sizes with one single purchase.

　　This canister costs just $80, which is competitive with those made by companies like BearVault. Its almost a two-for-one deal.

　　A Little Hefty

　　(Photo/Will Brendza) As soon as I picked this bear canister up, I was a little taken aback by its weight. For comparison, BearVaults BV500 Journey Bear Canister has a 700-cubic-inch capacity and weighs 2 pounds, 8 ounces. Thats the same weight as this REI canisters smaller 412-cubic-inch capacity configuration.

　　In its full 686-cubic-inch capacity configuration, the Traverse Modular Bear Canister weighs 3 pounds, 9.1 ounces. Thats comparable to products like the Counter Assault Bear Keg.

　　So, its on the heavier side, but it isnt breaking any records. If youre a gram counter, there are options that will appeal to you more. If you value versatility over weight savings, this is a great option.

　　REI Co-op Traverse Modular Bear Canister: Who Is It For? If you spend a lot of time backpacking in bear country and want one bear canister you can use for most of your adventures, its hard to beat the REI Traverse Modular Bear Canister. For a competitive price, this canister offers two size options for trips of different lengths, or with more or fewer people. The unique design is simple and easy to use.

　　(Photo/Will Brendza) Generally, I try to avoid words like revolutionary or groundbreaking, but they might be warranted in this case. REI took a thoughtful approach in designing this bear canister, and it came up with something no one else offers.

　　For its first bear canister ever, REI came out of the gate swinging on this one.

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