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  • Shape-Shift™ technology features a versatile baffle that can be zipped to slim the reservoir profile and unzipped to increase fluid volume or reverse to clean and dry
  • To clean, simply slide open, reach in, reverse, and rinse
  • High-flow bite valve with twist shutoff; Straight Shot Plug-N-Play connector allows easy tube removal while keeping the reservoir securely sealed
  • Durable, flexible thermoplastic polyurethane materials are BPA- and PVC-free, dishwasher-safe and naturally anti-fungal
  • All seams on the Hydrapak 3L Reversible Reservoir are welded to eliminate leaking


View all Hydrapak Reservoirs

REI membership


Best Use Hiking
Bite Valve Shut-Off Switch Yes
Wide-Mouth Opening Yes
Quick Disconnect Tubing Yes
Material(s) Thermoplastic urethane
Dimensions 16.5 x 6.75 inches
BPA Free Yes
Weight 6.9 ounces
Liquid Capacity (fl. oz.) 100 fluid ounces
Liquid Capacity (L) 3 liters
Rated 5 out of 5 by from easy to fill, easy to clean, seems durable I loved being able to fill it so quickly with the wide opening. There was a slight taste passed on from the lining, but it wasn't too unpleasant. The material feels durable enough that I wasn't worried about it getting punctured or damaged leaving it outside of a pack and lying on the floor of the tent, yet it's flexible enough to reverse without too much trouble. Unlocking the zip lock in the middle for reversing was a little more challenging that I anticipated, but once you get it started and know what you're doing it's not so bad. Closing it back up was pretty easy. Being able to reverse it to get it really clean and dry really differentiates it from other options. I would get it again!
Date published: 2014-09-20
Rated 5 out of 5 by from simple clean design, very user friendly This is the 5th or 6th different hydration sleeve I have owned and it is by far the best to date. The wide mouth makes filling easy. The very flexible material the bag is made from makes it incredibly easy to flip inside out for cleaning and drying yet it seems to be very durable. I also really like the fact that the hose is removable making installation into the backpack easy; no more having to work the mouth piece through the shoulder strap. I have used it a dozen times and would highly recommend it.
Date published: 2014-05-26
Rated 5 out of 5 by from very easy to keep clean I use energy drink in my bladders and previously had a lot of problems keeping bladders made by other brands clean. After 3 years of heavy mountain bike use, I've had no problems keeping this bladder free of mold due to its reversible design. I dry the outside, then turn it inside and dry the inside before hanging it up. I don't use the center connector (which also decreases the capacity) and that doesn't cause me any problems. I haven't had any issues with leaks or durability of the parts, but I did upgrade an older model to have the quick release hose, and it's nice you can buy just the parts to do this. I do put a little cooking spray on the O ring of the hose quick connect every once in a while to aid the connection, but otherwise maintenance free.
Date published: 2017-05-01
Rated 3 out of 5 by from Excellent design, durability lacking The design of this bladder is the best on the market. I was a huge fan for a few months. The only downfall, I thought, was that it is definitely not a 3L bladder. I bought this for a Rainier summit trek and found myself having to refill more often than anyone else in my group. When I filled the bladder by pouring 1L nalgenes into it, it could only take about 2 and a quarter. even when the middle zipper isnt done. Also, you have to underfill significantly if you want the top to close easily. After using this bladder for the past 6 months I have some concerns with its durability. The mouthpiece is very soft material and began leaking through a bitemark after about 3 months. I dont chew on it or anything, this was normal intended use. Lastly the other end of the hose, that connects to the bladder, has mysteriously been having a really hard time fitting into the valve. To be fair, I am a tour guide, so I use this bladder on hiking tours about 4 times a week. Heavier use that many. This is an excellent bladder. The material is strong, the design is great and once you get used to it it is very user friendly. I recommend it if 1) you do not need the capacity of a 3L bladder and 2) you are ok replacing the hose/mouthpiece twice a year. Enjoy David
Date published: 2015-02-13
Rated 5 out of 5 by from Solid hydration pack I bought this bag about a year ago and have been very happy with it. My previous hydration bag had a screw-on lid and it developed a leak at that spot. The Hydrapak has a closure at the top that folds over and you slide a bar across the top. It’s pretty rock solid with little chance of leaking. It is also easy to pour in and out of, and since it opens from the top you don’t have to take it all the way out of your backpack to refill. Its other big selling point is that it is reversible and easy to clean. We just bought a second bag for my wife just recently and the newer model had improved visibility of the volume indicator marks and they also added a little clip to make it easier to suspend. Unlike what an earlier reviewer noted, we can get three liters into our bags without problem. Drawbacks are that there is a ziploc-type rib closure down the center that gives it a slimmer profile (what they call “Shape-Shift” technology) but it’s hard to rezip after cleaning and really doesn’t serve a useful purpose. The hose is also a bit short, just barely reaching the chest strap on some of our backpacks. And one other small gripe is that the cord loop they have holding the sliding bar to the bag doesn’t look very durable. Still, it’s a great bag and I’m giving it 5 stars
Date published: 2015-07-30
Rated 1 out of 5 by from Doesn't hold 3 liters as you would expect! I purchased this hydration bladder allured by the ability to turn it inside out for cleaning and drying. As well as the wide mouth top filling feature. Both of these features are awesome and I would give it 5 stars EXCEPT that it doesn't hold 3 liters as you would expect! With the center part zipped the bladder only holds 2.5 liters. I never would have thought otherwise if I had not read about it in another review. I was curious so I measured the water in liters as I filled it with the center zippered and it only took 2.5 liters. I unzipped it and presto it took the other half liter for a total of 3. Now you might think no big deal just leave it unzipped when you want 3 liters, but the bladder is so bulbils when filled this way that it fits into the pack very awkwardly and made it hard to pack my gear. I will be returning this product and looking at other bladders with the same fill opening. Oh, the hose is also a tad short.
Date published: 2016-04-19
Rated 4 out of 5 by from Not 3L capacity but otherwise pretty good Let's start with the bad -- this bag doesn't hold 3l unless you unzip the center zipper, which is one of the reasons to buy it in the first place. So call it a 2.25-2.5L reservoir instead. With that said, it is otherwise ok. It fits in the reservoir location for my Osprey 65, it doesn't leak (and the top locks easily), it's easy to fill, the zip keeps it separated so it dries easily hung upside down with the zip piece stuck in the mouth to keep it open, and the hose/valve/etc piece works well. I found the hose long enough to reach where it had to go on my pack for on-trail use. It has a slight plastic taste when new, but it has faded. Durability has been fine so far; no problems. So all-in, the only thing I'm one star down with is the fact that it really isn't a 3L reservoir -- call it 2+ as I have gotten 2.5L in (measured) with the zip closed. Other than that it's a good choice.
Date published: 2016-09-30
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Is a cover for the bite valve included?

Asked by: Richard3613
​This reservoir does not come with a bite valve cover.
Answered by: REIservice
Date published: 2017-03-23

Several reviewers mentioned that the tube is too short for them. What is the length of the tube between connection points? Our local REI doesn't have this in stock.

Asked by: QN
The included hose is 36 inches long.
Answered by: REIservice
Date published: 2016-05-30
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