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Rated 5 out of 5 by from Not as bulky as you think! I purchased this bladder over a year ago and still feels new. I fill up my 3L and slide it into my deuter packs, I loved how this bladder is not long and bulky, but its rather flat for 3L. it creates usable space behind the bladder sleeve in my packs. Never a leak, also flip it upside down before placing in my pack just to be sure. The quick disconnect its awesome, and when reconnecting there is a very positive "snap". never going back to other brands.
Date published: 2014-10-23
Rated 5 out of 5 by from Great Product! I have used my trusty MSR Platypus for years ~ I never leave home without it. Whether out for an early morning Summer hike or snowshoeing/backcountry skiing in the Winter, this has been an outstanding product. Thanks for a great product from a Northwest native!
Date published: 2016-01-24
Rated 5 out of 5 by from Extremely comfortable while running and cycling I work with The North Face and it is a perfect fit for the majority of our backpacks and trail running vests. The problem with the long narrow bladders is that it rolls on the back and is an unnatural shape, they don't lie flat to the back. So when running or cycling, in activities with a lot of movement the new big zip is a lot more comfortable, the bigger contact area prevents the rolling, tubular feel and takes pressure off the centre of the back. With daypacks that have trampoline mesh backs, so the bag isn't actually in contact with the back, they tend to have a curve in their frame and my personal experience of these is that the long tubular hydration packs do not fit very well in them, they roll about and the bend in the backpack can kink the bladder, this wider, flatter design slips a lot easier into the sleeves of these bags and doesn't roll as much! Definitely you will notice a big difference, also the zip lock is so much easier to fill and wash than camelback screw topped ones.
Date published: 2015-04-29
Rated 3 out of 5 by from Where are the instructions? New to hydration systems so excuse my ignorance here. No instructions came with this product. I expected to see at least basic instructions on how to use, disassemble, clean and dry it. I figured out the most obvious features, but afraid to disassemble something I shouldn't. Found Instructions online for drying the bladder which said it was "easy" to do with a kitchen towel, but I don't have child sized hands, so getting a towel in there to dry it is impossible. I found no instructions anywhere for cleaning or drying out the tube. please advise!
Date published: 2015-10-12
Rated 5 out of 5 by from Why didn't I get one of these years ago??? I'm old to backpacking/hiking, but new to hydration bladders. I sure wish I had started using them years ago for hiking. Bottles just don't cut it anymore. The bladder is easy to pack, distributes the liquid weight way more evenly than several bottles that seem to move around in a pack. I chose the Platypus Big Zip 3L bladder over the one that was recommended by the manufacturer of my backpack because I liked the idea of the opening at the end of the bag, not in the center. I like the design and materials used in the BZ3 and the mouthpiece with valve is great! It looks well made and should last a long time.
Date published: 2015-07-22
Rated 5 out of 5 by from No bladder taste. This is the best tasting bladder I have. I have two other brands and 6 bladders total. It's easy to fill and clean. Since it opens up at one end it's also easy to dry out. The quick connect is a must have for some packs. It allows you to feed the hose in from the outside of the pack and connect it to the bladder on the inside without loosing any water. The 3 liter even fits in my pack that's only designed to take a 2 liter. I will be purchasing another one for my son's backpack.
Date published: 2014-12-28
Rated 5 out of 5 by from The best bladder i have seen I bought my Big Zip LP 3.0 over five years; it is still going strong. There are several features i love: -The zip closer it awesome -The quick disconnect is great, and allows the hose to swivel, and not kink -As light / compact as cheaper / thinner bags -Durable plastic and construction -Resistant to mold / discoloration -I like the 'tall' design of the older model. If my pack is shorter, i just don't fill the bladder all the way, and fold over the top. I do think the water has more of a plastic taste than it used to, but after five years, i can deal with it. I hope the design and quality continues
Date published: 2016-10-09
Rated 4 out of 5 by from Replace the bite valve I used a 2L antidote reservoir from Camelback for 2 years before getting this. I was drawn to how this reservoir opens across the top rather than a circle on the front. However, the bite valve is finicky and large. The larger size seems to pick up more dirt when you aren't careful with your bag at the crag. If you bite to hard (which doesn't take a lot) it won't give you a drop of water. If you bite too lightly, you get drips despite sucking your lungs out. It's not that hard to bite the right pressure, but it's precise enough that it's a pain to have to worry about it... especially while breathing hard. The tube is also very long. I keep mine in an 18L pack and the tube extends out the bag and down to my waist (I'm 5'11"). Luckily, to make this thing perfect, just cut the tube to the shorter length you want... and plug a Camelback bite valve right into the Platypus tube. Fills easy. Seals like a zip lock bag but much more heavy duty. Intuitive and has yet to leak on me.
Date published: 2014-08-18
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Questions & Answers

I would rather not drink out of the tube and I want the 3 liter size. Is there a way to make the water pourable? 

Asked by: Caro1980
for what purpose do you want this bladder? not sure this is a good fit if you're wanting it to pour well. whether you're wanting to drink from it or to use it in another manner, I'd look at either the platy hoser bladders (you can put a platy closure cap on them, instead of using the hose) or the platy soft bottles. platypus also sells water tanks in 2, 4, and 6L sizes although rei does not sell them
Answered by: heather
Date published: 2017-03-29

Just bought this - is there a technique to opening the white handle at the top to loop through the backpack loop to hold the bladder up?

Asked by: LeviLightfoot
​The white handle is not intended to be un-hooked.
Answered by: REIservice
Date published: 2017-02-28

I have the REI TRAIL 25 which has a hook for hanging the bladder on. Does this have a loop or something for the hook to go through?

Asked by: Mary
The reservoir has a white, plastic strip on the top that will fit into the hanger on the Trail 25 pack.
Answered by: REIservice
Date published: 2017-09-29

Would this be a good fit for an Osprey Talon 22 ?

Asked by: mountainbird06
​This reservoir will fit in the Talon 22 pack.
Answered by: REIservice
Date published: 2017-03-15

Hi, I have this and am wondering if there is a small backpack to go with it. I have a large backpack, but would like a small one that I could wear while biking.

Asked by: dragonmaki
Your Platypus Big Zip LP Reservoir - 1.5 Liter would fit nicely in a pack like the Osprey Talon 11: That pack and reservoir combination would be terrific for cycling.
Answered by: REIservice
Date published: 2017-09-02

Will the platapus 2liter fit in the Rei trail 40 or should I use the 1 1/2 liter

Asked by: Grumpy48
A REI Trail 40 Pack fits up to a 3 liter hydration reservoir. You are able to use either the 1.5 or 2 liter reservoir with this pack.
Answered by: REIservice
Date published: 2017-05-29
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