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  • Platypus - Big Zip LP Hydration Bladder - One Color

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  • Platypus - Big Zip LP Hydration Bladder - One Color

Platypus Big Zip LP Hydration Bladder

$34.95 - $36.95

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    • One Color, 2L
    • One Color, 3L

    87 Reviews


    Easy to remove, clean, and use.

    The Platypus Big Zip LP Hydration Bladder slides into hydration-compatible backpacks and maintains a low-profile when you're hiking, biking, or ski touring. Whether you refill the reservoir from a tap or water filter, the wide-mouth opening with Slidelock closure makes refilling the bag as painless as possible, while the treated lining prevents mold and bacteria from making your water taste like it just came from a swamp.

    • Stay hydrated on the trail with this reservoir
    • Wide-mouth opening makes cleaning and filling easy
    • Low-profile design sits comfortably in backpacks
    • Treatment prevents mold and bacteria from growing in bag
    • Angled shut-off valve prevents water from leaking
    • Made in USA with imported materials
    • Item #CAS0447

    Tech Specs

    1.5L, 2L, 3L
    quick release
    shut-off valve
    [1.5L] 13.4 x 7.9in, [2L] 15.6 x 7.9in, [3L] 17.2 x 8.8in
    Claimed Weight
    [1.5L] 5.4oz, [2L] 5.6oz, [3L] 6oz
    Recommended Use
    hiking, running
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Easy to Seal

    • Familiarity: I've put it through the wringer

    The seal on this hydration bladder is great. It's easy to fill, slips into my pack nicely, and doesn't leak because of the shut-off valve.

    CamelBak to Platypus, good decision

    • Familiarity: I've used it several times

    Finally made the choice to switch to Platypus, definitely a good decision. The CamelBak I've had for a long time got a hole in it and it seems a lot less sturdy than the Platypus. The new one I just got feels sturdy and awesome. Used it a few times MTB and hiking. The mouth piece is a little harder to get water out of than the CamelBak however it doesn't leak like the CamelBak that I had.

    Easy to refill to keep hydrated

    • Familiarity: I've put it through the wringer

    I reckon we all drink more water with a bladder than a water bottle--the straw is right there when you have a spare moment while hiking or riding. I am a HUGE fan of the Platypus Big Zip! The over-sized zipper closure makes it super easy to refill as you go, so you can stay hydrated while on the trail. The straw is easy to pop on and off, so you can keep the hose in place when you refill the bladder. Overall, this is an awesome and durable bladder I'd recommend to anyone!

    Awesome Bladder

    • Familiarity: I've put it through the wringer

    Durable and convenient, water bladders are the best way to stay hydrated on the trail. This one is very simple to use, has never leaked on my gear, and is still holding strong after a long spring and summer of putting it to the test here in the deserts and mountains of UT.

    Haven't found anything I dislike yet

    • Familiarity: I've put it through the wringer

    Basically the title. I love the opening and clasp. Easy to fill up especially compared to watching my buddy fill his camel. No problems with leaks yet.

    Awesome hydration bag

      The platypus 3L fits perfectly into most hydration compatible packs. I use this in my osprey 20L day pack for climbing and does the trick perfect! It is very simple and easy to use and clean! Five stars

      better than most

      • Familiarity: I've put it through the wringer

      I wanted a hydration bladder with a wide opening for cleaning and ice, and had heard these had no taste. The opening is good but I had hoped to be able to turn it inside out for cleaning and the baffle prevents that. The bite valve is not the best. You have to turn it to open it, and that's hard to do on a mountain bike. It leaks if you don't close it. Also the water does not stay all the way to the valve. But the water tastes great!

      Everything I need on the trails

      • Familiarity: I've put it through the wringer

      This bladder offers strength, I can confidently fill this at it's 3L mark, seal it up & hit the backcountry. I have it packed with my camera gear, sleeping bag & other important belongings & I feel safe with this bladder holding my water to keep me alive.

      Fast Drying And Easy To Clean

      • Familiarity: I've put it through the wringer

      I've used my Big Zip bladder for a few months now and it comes with me every time I'm wandering off into the woods. The big zipper makes it easy to fill, clean, and dry. I have nothing bad to say about the Big Zip bladder and the only reason I'm not giving it 5 stars is because the zipper sometimes doesn't zip correctly. Some people say this is a product error but it can easily be avoided if you pay attention to how it zips and flip it upside down to test it before putting it away.

      Fine, but there are better...

      • Familiarity: I've used it several times

      I have list of things I'm not stoked about, on this bladder. I strongly prefer Ultimate Hydration bladders. Read my reviews on them and reach out to me, if you have more questions.

      Great hydration bag

      • Familiarity: I've put it through the wringer

      Got this bag to use mountain biking, and hiking. It hasn't disappointed with repeated use. I would highly recommend this product!


      • Familiarity: I've used it several times

      I bought this after I had a camelbak 100oz reservoir start leaking. I was first going to buy another Camelbak until I saw someone using a Platypus bag at this concert I was at. I checked it out and immediately loved how small it can fold down into and how easy it is to refill and close. I also really like how the hose clicks in and attaches to the bag and that the bag doesn't leak when the hose is off it. There's no taste to the water unlike what I found with the camelbak after having the water sit in there for a few hours. It's super easy to slide the handle off, unlike the hassle found when trying to twist off/on the camelbak top. Overall I love this reservoir and would probably stick with this brand from now on.

      what are the dimensions of these bladders?

      Best Answer

      Hey Heather,

      Here are the dimensions

      2.0 L - 7in x 18.5in/weight 5.5 ounces

      3.0 L - 7.75in x 18.75in/weight 5.8 ounces

      If you have any more questions about this bladder or any other gear, please give me a call at 1-800-409-4502 ext 4446 or email at

      Can anyone comment on the flow from the...

      Can anyone comment on the flow from the valves between the Platypus and Deuter bladders? I have the UltraSpire bladder, which has great flow, but doesn't maintain pressure, so each time you want to drink you have to suck all the air out first. Terrible design, especially for runners.

      may I ask what is the advantage of this...

      may I ask what is the advantage of this type of system over a normal water bottle or canteen??just curious..I mean water in your pack equals wet gear and clothing does it not??Im not new to packing,just to all these new gadgets...

      Best Answer

      A few advantages:

      -- lighter weight to hold a larger volume of water

      -- The flat nature of the bladder is easier to pack and, when empty, takes up almost no volume in a pack (unlike a bottle)

      -- most packs hold these bladders at the ideal location for heavy gear (mid/high, centered, close to the back)

      -- the tube makes it easier to hydrate while moving. ("handsfree")

      -- The larger volume makes it easier when filtering/purifying water

      -- I like to hang mine up on a tree in camp, at which point it becomes a gravity-fed "faucet" for anything I need.

      All that said, I usually carry a bladder AND a 16oz insulated bottle. That gives me the versatility I like for drinking like a normal human, hot liquids, sharing, and my bottle serves as a tiny bear canister to store a midnight snack.

      I just want to add that most packs these days have a hydration sleeve to keep your bladder separate from the rest of your gear and the only way your gear is going to get wet is if you puncture the bladder which has never happened to me or anybody that I know personally.

      David and Wayne highlight great points. Weight is key, and this system is pretty light, even for a bladder. I personally own this system, and it does NOT leak (if used properly, of course). It even has a disconnect between the hose and bladder that allow you to remove/attach a full bladder with little (<1 tsp) to no water loss. I fully trust this bladder to keep everything dry.

      its light and you can fit a lot of water in a small area. however you are right it does suck when it leaks and every once in awhile that does happen, and I have had it happen more often with this bag then I have with other bags. however it is always a good idea to keep anything that you don't want to get wet in a dry stuff sack.

      Is the material the bladder is made of...

      Is the material the bladder is made of resistant towards boiling water, or will it change size due to temperature?

      I have never put boiling water in my own platypus, but the people in the thread below seem to say they have had no detrimental effects from putting boiling water in theirs. sounds like you should be set to go.

      will this fit in my clik elite camera...

      will this fit in my clik elite camera pack

      Hey Steve, we didn't carry that Click Elite Pack, so I checked around online. I'm not sure exactly which model you have. If it was the Express model with the computer sleeve for 15" Laptop or iPad, you will have ample room for any of the 3 sized Platypus bladders.

      The description of this bladder says "A...

      The description of this bladder says "A quick-disconnect fit on the end of the Platypus Big Zip SL Hydration Bladder's drink tube means you can easily remove the water reservoir from your pack without re-routing the drink tube"... so does that mean I *don't* need to purchase the quick-disconnect kit ( ) in order to tidily disconnect the hose from the pack? ie... it's already set up as is?

      Best Answer

      Correct. No need to by the quick disconnect seperado. The disconnect that is sold separately is to modify other hydration bladders to have a disconnect valve at the base of the bladder. But this bladder already has one.

      I have this backpack -- http://www.sears...

      I have this backpack -- but would like a 3L bladder. would this one work?

      Best Answer

      If you plan to use the built in bladder pouch, the 3L bladder is going to be too large. If you want to keep it in the large compartment and aren't concerned with it moving around a bit, it would fit. I think you'll likely have a bit of trouble fitting a 3L in the designated pouch no matter which bladder you go with.

      Can I use the new magnetic bite valve from...

      Can I use the new magnetic bite valve from my Osprey bladder with the Platypus Big Zip SL. Love the Osprey pack - don't like the bladder expect for the value. If I could make this switch this would make for hydration heaven... Thanks

      Ok, Whats the secret to freezing water in...

      Ok, Whats the secret to freezing water in the Platypus Bladder without freezing up the water flow in the quick-disconnect valve?

      Best Answer

      maybe place it in the freezer with the disconnect valve up. Then when you remove it, run the disconnect valve part under some warm/hot tap water to thaw out anything that might have frozen inside? Just a thought though. Haven't tried it.

      From the Platy site:

      How do I freeze my Platypus bottle or reservoir? Is it ok to freeze my Platy? bottle?

      Lay it half-full on its side in freezer with all air purged. Do not over-fill. Water expands as it freezes and this can burst your reservoir or bottle.

      Unanswered Question

      What size is best for Salomon Hydra Revo...

      What size is best for Salomon Hydra Revo Backpack?

      Can anyone tell me the weight of the 3L...

      Can anyone tell me the weight of the 3L bag only? Excluding the hose and the clip thingy at the top. Trying to save some grams from a gravity works setup and i think this would replace the dirty bag quite nicely asa it's a bit lighter. thx

      It's going to be difficult to get an exact answer on this because most people don't have a scale that reads that low. I'm sure it doesn't weight more than an ounce or two. It is just a thin plastic bag so the weight will be negligible.

      can you use the insulator hose accessory...

      can you use the insulator hose accessory with this?

      Absolutely! The Platypus Insulator Tube was made to be used with the Big Zip SL Hydration Bladder. It will also work with the Platypus Hoser Hydration Bladder. It's easy to install and works well to insulate in weather above 20 degrees F.

      Other than duct tape can you make repairs...

      Other than duct tape can you make repairs to this hydration pack? I have a pinhole leak after the first trip. Gy

      Best Answer

      You can use a repair kit made for a water bed or air mattress, but a better idea, if you can live without it for a week or two, is to take them up on their lifetime warranty. Cascade Designs warranty dept- 800-531-9531

      how do you dry this damed thing out?

      how do you dry this damed thing out?

      Take the cap off of a spray paint can, cut the end off the cap so that you have a cylinder open on both ends, then stick the cap into the bag's opening. This will hold the bag open better than any other method. Set it upside down for a bit so that most of the water drains, then clip it to something to hold it upright to dry the rest of the way.