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  • Osprey Packs Viper 9 Hydration Pack - 549cu in Go Green
  • Osprey Packs Viper 9 Hydration Pack - 549cu in Flashpoint Red
  • Osprey Packs Viper 9 Hydration Pack - 549cu in Wild Blue

Available colors

  • Osprey Packs Viper 9 Hydration Pack - 549cu in Go Green
  • Osprey Packs Viper 9 Hydration Pack - 549cu in Flashpoint Red
  • Osprey Packs Viper 9 Hydration Pack - 549cu in Wild Blue

Osprey Packs Viper 9 Hydration Pack - 549cu in

sale $79.96 $99.95 20% off

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    • Go Green, One Size
      Sale  $79.96
    • Flashpoint Red, One Size
      Sale  $79.96
    • Wild Blue, One Size
      Sale  $79.96
    in stock
    3.5 5 4

    4 Reviews


    Convenient hydration and just enough space for an extra layer and an energy goo.

    Whether it's an epic relay race, steep switchback trail, or a challenging cross country ride, trust your thirst-quenching needs to the Osprey Viper 9 Hydration Pack. The AirScape back panel and BioStretch harness keep the pack from shifting around during fast-paced pursuits and are ventilated to maintain comfort when you break a sweat. Even better, the full-featured three-liter Hydraulics Reservoir is shaped to match the contour of the back panel, which means better balance and less sloshing.

    • AirScape back panel provides cushion and ventilation for trail runs and cross country rides
    • BioStretch ventilated harness features EVA foam padding and spacer mesh for next-to-skin comfort
    • 20mm webbing hip-belt keeps the pack balanced and in place
    • Pack size fits a compressible windbreaker and a small snack
    • Separate hydration sleeve provides quick access to the reservoir
    • Three-liter Hydraulics Reservoir features a HydroStatic backer plate that maintains a low-and-wide profile, preventing interference with your pack's suspension
    • Reservoir is made from metallocene PE material that is exceptionally strong, taste-free, and BPA- and PVC-free
    • LidLock clip allows you to quickly attach your helmet when not in use
    • Stretch mesh front pocket is ideal for stashing a rain jacket or extra layers
    • Main compartment has pump-specific sleeves
    • Top zippered pocket has a soft embossed fabric for stowing sunglasses and electronics
    • Magnetic sternum buckle pairs with the magnetic bite valve to keep the hose secure while riding
    • Item #OSP0311

    Tech Specs

    210D polyester, 600D polyester
    Reservoir Volume
    3 L
    [external] 1 front shove-it, 1 zippered sunglasses, [internal] pump sleeves
    Locking Bite Valve
    Claimed Weight
    1 lb 2 oz
    20 x 9 x 7 in
    549 cu in
    Recommended Use
    mountain biking, trail running, day hiking
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Great fit for a "unisex" pack

    • Familiarity:I've put it through the wringer

    I'm 5'3" and the pack fits me just fine. I don't have a very large chest area so perhaps those who do, would need a women's specific hydration pack. The shoulder straps are very comfortable and I love that the bladder hose zips right into one of the straps to keep that stored away. There's also a little magnet that keeps the mouth piece attached right at the chest area for easy access. There are lots of pockets which sometimes I don't know what to do with them all! This is such a great pack, I'd recommend it to anyone. I have the 'Gunpowder Grey' color and love the neon-ish green accents.

    5'5" Female - Rubbed Neck

    • Familiarity:I returned this product before using it

    I loved everything about this bag until I tried it on. I instantly could feel it rub the back and sides of my neck. Otherwise, this bag is awesome... I had to return it because I knew that would bother me horribly as I began biking or hiking.

    I have last year's Viper 10 and I love it,...

    I have last year's Viper 10 and I love it, is this pack worth the upgrade regardless of the money? What does anyone out there who has it have to say about it?

    Best Answer

    Also, you can go directly to, and do a compare for both the current model, and the previous years' models.

    Click on "past seasons" on the model you're interested in...then look at the speck on the tab at the top of the window.

    Then you can compare to the current season's model to see what, if any, improvements have been made.

    Hope this helps!