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GSI Outdoors Flask

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    17 Reviews


    It’s like a sweater that you wear on the inside.

    Whether you’re taking a warm-up nipper or starting a full-on camp party, the GSI Flask is an indispensable tool in the backcountry boozer’s toolbox. Made from super-strong, BPA-free resin, this flask stows easily in your pack or cargo pocket and features a convenient shot glass cap for throwing a few back after a long day on the trail.
    • Item #GSI0150

    Tech Specs

    BPA-free resin
    18 oz
    Claimed Weight
    113 g
    Recommended Use
    backpacking, camping
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

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    The perfect flask

      I love this flask when I'm in the outdoors. Holds 18 ounces and doesn't leak. The Stanley Flask I had leaked ever so slightly. While the brain of my pack did smell of delicious bourbon I was bummed on the loss of whiskey. Would highly recommend this outdoor specific flask.

      Depends on where you want to take this

      • Familiarity: I've used it several times

      I took this to a couple camping music festival and this is a great flask for sharing or consolidating drinks. It does not leak and easy to open and close. But for solo trips up into the mountains I felt it was a little to much to carry and made it too easy to drink from. #hangoverssuck

      Had it. Lost the cap.

      • Familiarity: I've put it through the wringer

      Ok, so I lost a flask cap...probably not the 1st time in history this has happened. I would recommend that GSI add a cap connector type thingy! This holds some serious volume and I actually found it to be too bulky. Great for what it does though!

      Great flask

      • Familiarity: I've put it through the wringer

      Took this on most of my NH 4000 footer trips and usually use it for whiskey on multi-night trips in the summer when beer isn't an option. Also used it for water while snowboarding in either a large jacket pocket or a cheesy backpack. The concave bottle contours to your spine. I used this on a trip this summer for a sidepeak water bottle after we drank all the whiskey and lost it coming down Owls Head so I need a replacement. Lasted me about 3 years, definitely earned some scratches from tossing it to freinds on summits but it never broke or leaked. I also bring this on trips where there is only a little booze left and I don't feel like lugging a big glass bottle back. Works equally well for wine also or use it to mix powdered gatorade in if you use a water bladder. If you prefer ultralight weight this isn't for you but then again neither is whiskey or huge balls of steel.

      Not your average flask

        The display photo does not do this thing justice. Take a look at Michael's pictures below for a better idea. This flask is taller than a nalgene and holds 18 oz of your spirit of choice. It doesnt leak so I use it for camping/backpacking when I dont want my clothes and other gear to get soaked in booze. The rubber o ring in the cap works like a charm, but because of the overall size of the flask it is not ideal for inconspicuous carry.

        Didn't leak, holds a lot

          This is a great bump-to-free-shipping item, and it's actually pretty useful. It holds enough liquor for a few people to share over a multi-day trip, if you're just having a drink or two each night. Alternatively, it holds plenty for a single person over a couple days if you're hitting it hard. Either way, 18 ounces is a good bit of liquor, and it hasn't leaked on me yet.

          Great Flask!

            My wife and I just got back from a couple nights out on the beautiful Florida trail. It was great having this along with us to have a little something to nip on after dinner while getting cozy around the fire. We actually have the 10 oz size instead of the larger 18 oz size sold here. The 10 oz size is perfect for the two of us, but since the weight difference between the two of them is really negligible, if you have room in your pack I heartily suggest going with the larger one. As others have noted, this container imparts no extra taste to the contents. It seals up very well, is much lighter than a traditional stainless flask, and the wider mouth makes it much easier to fill (and to empty!)

            If you enjoy whiskey, but might also like something sweeter, there is a great product that my wife and I enjoy very much. It is called American Honey. It is almost TOO good. It's a great drink to warm you (and your significant other) up on a cool night around the camp fire. It is a requirement whenever my wife and I hit the trail.

            Bigger than you might expect

              Most people have commented on the size and it is definitely bigger than the pictures make it out to be. A standard flask is about 8 oz, so this thing is more than double that size. That said, if you plan on taking more alcohol, 18 oz will do some pretty good damage among a few guys. This this will hold nearly 3/4 of a fifth of booze. I usually just bring this along when there's multiple people and we're staying a couple days. Otherwise, the standard 8 oz flask comes with me.

              Cheap, doesn't leak and odor free

                Like others said already it's surprisingly big, but that just gives you the option to part fill or completely fill to manage the weight. The size is no problem if it's in my pack. Certainly not a flask to carry in a pocket. It's cheap, doesn't leak and there is no odor from the plastic. From there the flask can be judged by the quality of what you put in it.

                Be Sure to Check the Cap Gasket!

                  It appears to be a nice functional design but mine leaked in my pack. I discovered the O-gasket seal in the cap moves out of position when tightened. I thought it was an isolated case but when the second flask did the same thing, I replaced it with a 16oz Nalgene HDPE narrow mouth screw top bottle & the problem went away.

                  Good camping flask

                    Took this guy camping a few times so far and have been pretty well impressed at how it's held up. Be advised; it's MUCH taller than the photo on here makes it out to be. Surprisingly taller to be honest. Holds a LOT of liquor. It cleans very well, (I agree with the below reviewer with the fact that the body of the flask doesn't hold a lot of odor, however the cap has a tendency to do so. I believe this might be because of the small gasket.) Speaking of that gasket, I would have rated this more stars than I did, but that little malleable gasket in the cap has separated and come loose. I expected that this would happen over time but was surprised at how quickly it came loose after two instances of "field" use.

                    Overall, while it does fill the bill and is useful, I'm thinking about trying another flask from a different manufacturer and moving this into more of a backup role for my camping kit.

                    Simple and dependable.

                      Leakproof screw on top,durable and thin profile... and cheap! These don't hold odor at all really- They would if you left some booze in there for a month after your camping trip, but it's really nothing to worry about. I dropped a full one about 10 feet onto hard granite-- just a scratch. They are a little taller then the product photo would indicate- About 8" tall I'd guess w/o having it in front of me.