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Osprey Manta 25 Hydration Pack - 100 fl. oz.

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  • Osprey Hydraulics™ system sandwiches an anatomically shaped plastic sheet between a layer of nylon fabric and the reservoir back
  • Design conforms the reservoir to the back's shape even when full, resulting in a precise, stable and comfortable fit
  • Reservoir features a rigid spine/handle that stabilizes the water load and makes it easy to slide the reservoir into the pack
  • Rigid spine/handle and large mouth make filling and cleaning the reservoir a snap
  • BPA- and PVC-free reservoir does not retain tastes or odors and features AquaGuard™ antimicrobial formula to help prevent bacteria and mold
  • 180° pivoting on/off valve rotates in either direction for quick and easy flow control; magnetic sternum-strap buckle secures the bite valve when not in use
  • AirSpeed™ suspension incorporates a lightweight alloy frame and cross struts with a tensioned mesh back panel for support and flexibility
  • Mesh and perforated, molded waffle foam at contact points along shoulder straps and hipbelt enhance breathability and comfort
  • Panel-loading main compartment is spacious enough for your done-in-a-day food, clothing and gear
  • Zippered front organizational pocket with key clip holds small items; zippered top pocket with soft lining helps keep sunglasses or other fragile items from getting scratched
  • Stretch-woven front pocket offers quick external storage and access; integrated patch holds a blinker light (sold separately)
  • Zippered side pockets carry small items within easy reach
  • Zippered pocket on hipbelt keeps small essentials handy
  • The Osprey Manta 25 hydration pack features an integrated raincover that can be quickly deployed to keep contents dry


Item 796762

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Osprey Manta 25 Hydration Pack - 100 fl. oz. Specs
Best use
22 / 25 liter
1,300 / 1,500 cubic inches
3 liter
100 fluid ounces
2 lbs. 11 oz. / 2 lbs. 14 oz.
1.22 / 1.30 kilograms
<19 / 19+ inches
<33 / 33+ inches
Metal alloy peripheral hoop/EVA backpanel
6 + main compartment
19 x 10 x 10 inches
Frame type
Gear capacity (L)
Gear capacity (cu. in.)
Liquid capacity (L)
Liquid capacity (fl. oz.)
Weight - metric
Adjustable torso
Fits torso
Fits waist/hips
Frame material
Pack loading
Number of exterior pockets
Bite valve shut-off switch
Quick disconnect tubing
Wide-mouth opening

Osprey Manta 25 Hydration Pack - 100 fl. oz.

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Rated 4.5/5 based on 30 reviews
Rated 2out of5
by fromI really wanted to love it, but.... The construction and design of this bag are both stellar. From the hydration bladder (no more fussing trying to cram a flopping 3L of water into a skinny pouch), to the multitude of pockets. But this pack didn't do the one necessary thing I needed it to- fit comfortably. The metal wings at the bottom of the frame dug into the small of my back. No matter how I tried to fit it, they dug in. I've had 3 different people try on this pack, and they all agreed- the frame needs re-tuning. Stable- yes. Comfortable- no. My advice- try it on before you buy, and make sure it fits you well.
Date published: 2010-05-23
Rated 2out of5
by fromManta 25 review As others have stated, the design of this pack is great. Quality materials and a really nice layout. But advertising this pack as having 25 liters of volume is simply misleading. It is surprisingly small and I have the med/large version. I wanted to use the pack to carry a change of clothes. 1 pair of shoes, 1 pair of shorts, 1 t-shirt, and 1 pair of socks. After putting a pair my size 10.5 New Balance in the main compartment, it was pretty much full, but not having another compartment on the pack big enough to put my shorts in, I had to literally jam them into the main compartment with the shoes. With the shoes and shorts in, it was stuffed. I put my t-shirt in the pouch on the back, and put the socks in one of the little side compartments. The pack was full, and I would expect a 25 liter pack not to be so stuffed with just these items. The pack would be great for carrying a handful of small items, but if you put an item in there that has any size to it (shoes, jacket, pants) you're not going to get much more in the pack. So if you require a pack that really has 25 liters of volume, I can't recommend this pack.
Date published: 2010-09-06
Rated 3out of5
by fromGet the 30L The features on this pack do live up to the hype, I really like the reservoir design the spin and back panel work well, the pack is comfortable and light. The materials in the pack are high quality and the rainfly works well. My major issue with the back is that it holds less gear than my 18L camelbak. I have the small/medium so it supposed to be 23L, but I'm doubtful that it is I wish I would have purchased the 30L. If you don't carry much gear this may be the pack for you, but I like to carry a group med kit, jacket, extra food, and a few other small items. I really can't carry much more than that if I wanted to, its not bad for a long day hike, but I would like the flexibility if I was going to use it somewhere cold. I squeezed my climbing shoes in there once as a trade off for the jacket.
Date published: 2010-03-29
Rated 4out of5
by fromLove it Great pack, very well thought out. The only mistake I made was overfilling the hydration reservoir which resulted in a leak. The next time I didn't fill it up passed the hole and it was fine.
Date published: 2012-09-26
Rated 4out of5
by fromNice Sack! Great pack for day hiking or trail biking, light, plenty of storage, well designed.
Date published: 2013-02-20
Rated 4out of5
by fromBetter than anything else I've found I'm a 5'3" woman, which can make fit tricky. I use this pack for dayhikes only. I don't climb or scramble - just hike. The Manta 25 in sm/med has all the features I wanted. The hip-belt pockets are just right for my camera and other small stuff. Compared to my Camelbak Blowfish, this pack is better organized, the bladder is easier to fill and install in the pack, the bite-valve is easier to use and the pack is just plain more comfortable. The magnet to keep the bite-valve out of the way but still convenient is a nice touch. Other features I was looking for and found in this pack include a rain cover and external unzippered pockets (good spot to keep your maps). One reviewer mentioned the metal frame at the corners, and I had to go check my pack to even know it was there. Capacity may be a little on the tight side, but you can use the external loops and a tie-down or two to hold that extra jacket you had to take off halfway up the hill. The only thing I would change is make it easier to tie stuff to the outside. That's the 'lack of flexibility' in the cons notes.
Date published: 2010-07-11
Rated 4out of5
by fromcomfortable, but small This narrow pack fits well and does not feel constricting. The narrow profile allows for a wider range of arm movement. I am 5'11" and could not get the pack to adjust so that the hip-belt is on my hips. It sits more around my waist, but that is not such a big deal since there isn't much capacity to carry anything too heavy. Even though the capacity of the pack is 25L, the shape it is in makes for only about 15L of useable space in the lower portion of the bag. I fit a DSLR camera with lens and a a towel in there before it was fairly full. Fitting a pair of hiking boots in this would be a very tight squeeze. Even if you are able to fit something inside, the bulge from the hydration pack limits access to the bottom of the bag while on the go. I had to stop on the trail, unbuckle the side straps and shift around the pocket contents until I could reach the camera. The overall pack is bulky for how little usable volume there is. I think this pack would be more suitable for carrying a first aid kit, a backpacking stove, some food, and other things that you might need once you stop. It is not good for storing anything that needs to be frequently accessed. That being said, there are plenty of loops to clip a GPS, cell phone, sunglasses, hat, etc. to. Just not able to carry them inside. The rainfly is a nice touch, but it functions like a large showercap and does not have any secure way to fastening to the pack other than elastic. Also worth noting is that the hydration bladder opening is not a standard size for water filters to connect directly into. This pack takes a lot of getting used to, but it is well constructed and is comfortable to use.
Date published: 2010-12-27
Rated 4out of5
by fromGreat Pack This feature loaded backpack has seen me through several day hikes and long bike rides. It is light, comfortable, and large enough for any adventure you can dream up for a day, short of trad/sport climbing. Not sure its quite big/robust enough for a trad-rack and rope… ect. Osprey did a great job trimming ounces from this pack while preserving functionality and comfort. The shoulder straps are super light weight but reasonably well padded for comfort. The shoulder straps are also well ventilated (as is the back) to allow cooling evaporation in hot weather. I did notice that the straps left some abrasions on my shoulders after a 14 miler earlier this summer, but that is to be expected with any pack. I made this pack ready for the trail by adding one of Osprey's Grab Bags, a cool add on that gives the user an additional pocket across the chest. I did, however, have to swap out the webbing to keep the super functional magnetic sternum clip (are you taking notes Osprey??? it would be awesome if all the clips were interchangeable!). I also added a safety light on the back for visibility when I am riding or hiking at night.
Date published: 2011-07-17

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