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Osprey Viper 13 Hydration Pack - 100 fl. oz.

$92.93 $109.95*

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  • Hydration system features a 100 fl. oz. reservoir that conforms to back's shape even when full, resulting in a precise, stable and comfortable fit
  • Rigid spine/handle stabilizes the reservoir, making it easy to slide it into its dedicated compartment; large mouth makes filling/cleaning easy
  • Hydration reservoir pocket has zippered access that extends onto shoulder strap, letting you remove, refill and replace reservoir and drink tube quickly and with minimal fuss
  • Low-profile padded mesh back panel and mesh shoulder straps offer next-to-body comfort; sternum strap has a magnetic attachment for keeping bite valve accessible
  • Large zippered main pocket with tool organization sleeves and a mesh pocket is ideal for carrying pumps, bike tools and tubes
  • Front zippered pocket has additional mesh pockets for more organizational options; key clip secures keys
  • Stretch mesh front and side pockets work great for stashing extra gear or water bottles for quick, easy access
  • Quick-access top zippered pocket is lined with a soft, easy-to-clean heat-embossed fabric that helps keep sunglasses or other fragile items from getting scratched
  • Quickly attach a helmet to the Viper 13 with the LidLock™ helmet clip; bungee on the exterior of the pack allows easy adjustment of the LidLock feature
  • Shove-it pocket can be cinched down to secure bulky items like a jacket
  • Top and bottom side compression straps help stabilize pack and contents; removable webbing waistbelt helps stabilize pack
  • Reflective trim increases visibility in low light
  • Osprey Viper 13 hydration pack sports a BPA- and PVC-free reservoir that does not retain tastes or odors and features an antimicrobial treatment that deters bacterial growth

Imported.

Two multi-day hikers in Osprey packs gaze over a desert landscape

Take a technically stunning Osprey pack on your next hike, or trip around the world.

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Best use Mountain biking
Frame type Frameless
BPA free Yes
Gear capacity (L) 13 liter
Gear capacity (cu. in.) 793 cubic inches
Liquid capacity (L) 3 liter
Liquid capacity (fl. oz.) 100 fluid ounces
Weight 1 lb. 4 oz.
Weight - metric 0.55 kilogram
Fits torso 17-21 inches
Fits waist/hips Unavailable
Material(s) Ripstop polyester/polyester
Number of exterior pockets 4
Hipbelt Yes
Bite valve shut-off switch Yes
Quick disconnect tubing Yes
Wide-mouth opening Yes
Dimensions 20 x 9 x 8 inches
Gender Men's
Average rating

4.6

(5 total reviews)

What do you think of this product?

Share your thoughts with the REI community.

  • Reviews. Average Rating is 3 stars
    Osprey Viper 13L
    I have a deuter act trail 32l but never utilized its purpose because i thought it was too big for my daily/casual use. so i looked for a smaller one. i've watched and read several videos abo...
    Read More
    I have a deuter act trail 32l but never utilized its purpose because i thought it was too big for my daily/casual use. so i looked for a smaller one. i've watched and read several videos about minimalist backpacking and one of these took my attention. in the video, the guy from canada uses an osprey viper 13l on his travelling to costa rica.he stayed there with his 13l pack for a month. all of the essential were there and if it comes with the bare essentials as far as my preferrence is concern, 13l for me is convincing. inside his pack is a foot-curved like slippers. 2 compression sack, mini medical kit. recheargeable headlamp .small knife. bandana. spork. toiletries(dental floss and toothbrush only). whistle. padlock. clip. phone charger. watch. 1 underwear. 5x8 tarp. belt. sweater. jeans. rain jacket. towel. swimming trunk. pair of socks. a book. journal. phone. wallet. pen. and that's it!. because of that i thought it will work as well for me as a daily pack or minimalist travel backpack as long as i compromise to the things that i would normally prefer to bring. with that i decided to have one and make it as my all day all situation pack. as of now it feels great. the back system is really comfortable. i didnt notice that there something hanging on my back. i havent tried to pack it full yet. so there's a reservation. i didnt use the hydration bladder as i prefer to use a small bottle. it fits well on the side mesh pocket. when it comes to durability i cant say a lot for now. i need to grind it more often to see the result. i got the gunpowder gray because of the tough rugged color style. so for now i'll rate it 3. but i'll update my review after 3 to 4 month or if anything happen that you need to know. cheer!
  • Reviews. Average Rating is 5 stars
    The perfect pack for me
    I was looking for a pack to carry specifically on my bike rides, and this pack fit the bill. I've tried other hydration packs, and have been disappointed numerous times due to the short shou...
    Read More
    I was looking for a pack to carry specifically on my bike rides, and this pack fit the bill. I've tried other hydration packs, and have been disappointed numerous times due to the short shoulder straps. The size compared to the amount of water is a major bonus as well.
  • Reviews. Average Rating is 5 stars
    Great find!
    I was planning on replacing the bladder of an old hydration pack when when my 10 yr old son spotted this pack on clearance. It was only $15 more than the 3L platypus bladder. I'm so glad he ...
    Read More
    I was planning on replacing the bladder of an old hydration pack when when my 10 yr old son spotted this pack on clearance. It was only $15 more than the 3L platypus bladder. I'm so glad he did! I took this pack on a 135 mile bike ride and it had enough room for all my gear, snacks and most importantly, water. I like the rigid backing on the bladder. Very comfortable. I made a mistake and put the bladder in the pack backwards and the spine dug in to my back. But when in properly, it was fine. No sloshing from the water in the bladder. The magnetic tab on the sternum strap kept the mouthpiece in reach. The pack was stable when fully loaded. Felt really light on my back. It also has great circulation. I never felt a wet spot on my shoulders and back. Love the green color too :)
  • Reviews. Average Rating is 5 stars
    Perfect for the long or short ride
    This thing is great. It has plenty of room for the gear (co2, shock pump, tire pump, tools and tube). The Bladder is huge 3L......enough for a full day of riding. I love the Helmet attachme...
    Read More
    This thing is great. It has plenty of room for the gear (co2, shock pump, tire pump, tools and tube). The Bladder is huge 3L......enough for a full day of riding. I love the Helmet attachment feature so it's not bouncing around. The magnetic attachment for the bladder hose is in great. It keeps it secure, and out of the way, but easy to access while riding. Have used this all summer and have no regrets.
  • Reviews. Average Rating is 5 stars
    Excellent all around biking/hiking pack
    Bought this for mountain biking but I use it for hiking as well. The pack itself is designed for biking with pockets and features specific for that genre. This pack is very comfortable even ...
    Read More
    Bought this for mountain biking but I use it for hiking as well. The pack itself is designed for biking with pockets and features specific for that genre. This pack is very comfortable even when filled completely, and I'm pretty picky when it comes to pack comfort. I've always had camelbaks so I wasn't sure about the Osprey hydration system. I'd say there are some pretty good pros to it such as the stiff backing to the bladder (awesome feature!). There are also some cons such as the lid is harder to get on than the camelbaks, but once it is on it doesn't leak. I also like the big bite valve on the Camelbaks a bit better, but the Osprey one is fine. The only con to the pack I can think of is that the magnet piece on the valve doesn't really stay attached to the sternum strap magnet when you have it buckled because the tubing isn't long enough. Other than that the pack is amazing and the green color is pretty sweet. I also checked out the mantra and the raptor. I like the mantra, but liked the design (the pocket arrangement and the way the hydration zips in) and size of the viper better. The raptor was cool, but seemed to built more for long distance road bikers with the built in tool chest.
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