Not currently available at any of our online partners
Complete the System
Add Item To Wishlist.


Osprey’s Hydraulics™ 3L Reservoir by Hydrapak® is ideal for large volume packs and long duration activities. The HydroStatic™ backerplate provides structure for easy loading into a full pack and maintains a flat profile. Thoughtful design makes filling, cleaning and most importantly staying hydrated on the trail easier than ever. All parts are BPA-free, phthalate-free, lead-free, guaranteed. All materials are certified food safe according to FDA and EU regulations.


  • Hydrostatic™ Backerplate - Hydrostatic™ backerplate provides structure to shove a full reservoir into a fully loaded pack and maintains a flat profile.
  • Slide-Seal™ - Easy Slide-Seal™ top opening, seals watertight and provides wide access for easy filling and cleaning
  • Pour Shield - Pour shield extends the collar to ease filling in shallower sinks and control pouring into pots or bottles
  • Carry Handle - Carry handle allows easy reservoir management and filling
  • Magnetic Bite Valve - Magnet clip attaches to the reservoir hose and pairs with the included sternum strap magnet for easy water access and hose management
  • Hydrapak® Blaster™ - Hydrapak® Blaster™ bite valve offers fast, smooth water flow with a ¼ twist on/off switch
  • QuickConnect™ System - The QuickConnect™ system allows easy removal/filling of the reservoir and filtering in the backcountry


  Volume Dimensions Weight
O/S 100 in3 / 3 l 15h x 7w x 3d in. 0.68 lbs.
O/S 100 in3 / 3 l 39h x 18.5w x 8d cm 0.31 kg
TPU film
TPU film
TPU film
Product Manual Additional languages available here �
Hydraulics™ Reservoir Product Tour


Makes the water taste like liquid plastic


I rinsed it out, filled it, put it in my new Osprey Aether 70 and went out overnight in the Superstition Mountains. The chemical / plastic taste of the water was awful. I never had this issue before with a new hydraulics reservoir. All else is good, but if I can't get that taste out it's going straight into the garbage. I'm giving it a 1 star because it tasted that bad, and I was stuck with it for 2 days.


Does not fit into pack.


I got this for my new Aether 70 ag. Little did I know if you fill this thing up. There is no way you are going to get it into the sleeve on the pack. So I filled it with 1.5 liters of water. It was still all I could do to get it in there. It's not going to last long like that. The 1.5 liter reservoir may fit but this 3 liter does not. Not even close. Also I do not like that it takes two hands to open the bite valve. I may try a 1.5 liter. Anybody want this 3 liter before it springs a leak? I've only used it once and probably the last time. It's a great idea for convenience but I hike in the South. There is water almost everywhere.

Tamassee, SC

Best one till date


The pack goes in my Trekking Backpack. This Hydration Pack is the best of the previous packs I have used, till date. Perfect in every way. It is light weight yet sturdy. The backerplate keeps the pack upright till the last drop of water. Just one Feedback, it would be nice to have a 'loop-like' thing on the base of the pack. This will help one to hang/hook the hydration pack 'upside down' after washing. It will drain the water droplets quickly.

Mumbai, India


Used for 9 months backpacking and loved it


I used this reservoir for 9 months of backpacking around south america, and really liked it. It's easy to clean, easy to slide open and close, I like that the hose snaps on and off so that it's compatible with the Katadyn water filter (yay for not company specific design!), the bite valve doesn't fall off easily like Camelbak's, and the rigid back makes it easier to slide into a full backpack. Yes, it takes some finagling, but it fits into both my daypack and large backpacking pack. The only reason I'm not using it right now is that the O-ring popped off when I was taking it out of my backpack in the amazon, and I couldn't find it. Once I replace it, I'll start using it again.



Bring back the old version...this thing is terrible!


Oh Osprey...you really missed the mark with this one. The old blue version was so great...easy to fill because it was rigid with the long handle that also helped guide into any of my 4 Osprey packs and it never leaked. Unfortunately everything fails in time and something poked it and it sprung a leak...not Osprey's fault. This new version is junk at best. First of all, you have to try to hold the sides or lips of the reservoir open to fill but since it isn't as rigid so you can't hold the wimpy handle and fill it so it's a challenge not to spill water everywhere. Secondly, once filled with 3 liters of water, you cannot get it all the way down into the hydration sleeve on a Stratos pack, it stops halfway down and you have to force down even on an empty pack and hope it doesn't bust open. So now that ridiculous useless mesh pocket on a Stratos (another major fail) is not usable either. I've tried to use my other hand to guide the reservoir down into the sleeve and it's nearly impossible. Even on actual hydration packs like a Manta that have a dedicated hydration compartment, it's hard to get in and out with that wimpy plastic excuse for a handle. Lastly, just know that it's going to bust open or leak pretty soon after using, which it already has within a couple of weeks of being VERY GENTLE with it so now it's useless. I know this new version is fashionable to some and seems like a good idea on paper but if they actually did any product testing like most of the reviews on here...they would have never allowed it to be sold. Major fail Osprey...love your products but this was a waste of my hard earned money. Even a bad Camelbak bladder is better than this thing. Thanks for nothing.

Scottsdale, Arizona


I miss the old design


I've had a Raptor 14 for years now. I initially bought an extra bladder for my endurance races. Later I purchased a third bladder to have as a spare. It is the new fold over design vs the older screw top design. Overall I am not a fan of the new sealing method. I've used my 2 original bladders almost every day for 3 years and have never had an issue with them sealing. The biggest downside is that the new design holds substantially less water. Overall it is still functional seems durable but I'd pay more for an old style unit.


Well it's great until it starts leaking at the base


Well I LOVE the Osprey 14 pack but the bladder is really bad, it's opening is very small (which I can live with) but they start leaving often. I am on my 3rd one and they all start leaking around the base. Epoxy works for another month then total failure. For a product this expensive it should last. Again the pack is excellent.

Lake Tahoe

New is not better


I have both an Atmos AG 50 for day hikes and purchased an AG65 for extended hikes. I have an older style 2 litre bladder in the AG 50 and a 3 litre bladder in the AG 65. The design of the 2 Litre old style with screw on cap is far superior to this new style! 1. The plastic support clip broke on the second hike. It is not strong enough to support 3 litres of water. 2. It is more awkward to fill and, due to its full shape, takes up too much room. 3. Following on with point 2, the old style is both longer and wider meaning when full, the shape does not push into the pack storage area as much as the new 3 litre version. 4. Plastic feels less durable. Still getting bad taste; did not experience this with the earlier bladder. 4. Pros are that it weighs 35 grams less than the 2 litre screw cap version. 5,. Comes with a quick release tube (which I also retro fitted to the screw cap 2 litre version. Summary, look elsewhere, not suitable for its intended purpose.

Melbourne Australia


I like the older styles better.


This is the third generation of hydration bladders that I have owned from Osprey and I prefer the older styles for a couple of reasons. 1. I find it difficult to hold while filling. 2. It is a lot narrower than previous bladders which makes it thicker when full. This makes it difficult to load it into an already loaded pack and takes up valuable space. Would love to see a wider, thinner bladder. It is way easier to clean and I do like the new mouthpiece design.

Gatlinburg, Tn.


Like the top closure better than the old version


I need the large capacity for desert backpacking. The hook is not strong enough for the 3L of water and broke the first use. Also, the hose turned yellow and I only use it for water. I DO like the new system of filling compared with the old screw-on lid that would never align right and lose water. It is also lighter than the older version. I like the hose disconnect to allow for easier fill. I do not like needing two hands to open bite valve.

Provo, UT



2.9 19


Notify Me