• Online:
  • URL for this product:
  • From the U.S. and CanadaCall 1-800-426-4840
  • Mon. through Sun., 4 a.m. through 11 p.m. PT.
  • InternationalCall 1-253-891-2500
  • Mon. through Sun., 4 a.m. through 11 p.m. PT. English language only.
Amphipod Full-Tilt AirStretch Velocity Hydration Waistpack - 20 fl. oz.


    Amphipod Full-Tilt AirStretch Velocity Hydration Waistpack - 20 fl. oz.

    The Amphipod Full-Tilt AirStretch™ Velocity hydration waistpack offers a lightweight design and a low profile that help eliminate the discomfort of traditional bottle packs. See details

    • $29.93 - $39.95

    Item # 813463

    The Amphipod Full-Tilt AirStretch™ Velocity hydration waistpack offers a lightweight design and a low profile that help eliminate the discomfort of traditional bottle packs.

    Product size and color

    The Amphipod Full-Tilt AirStretch™ Velocity hydration waistpack offers a lightweight design and a low profile that help eliminate the discomfort of traditional bottle packs.

    • 100% Satisfaction Guaranteed
    • Gear and Advice You Can Trust

    Orders of $50 or more ship for free.
    Learn more

    To view videos or use the zoom feature on REI's websites, please download the latest version of Adobe Flash Player.


    The Amphipod Full-Tilt AirStretch™ Velocity hydration waistpack offers a lightweight design and a low profile that help eliminate the discomfort of traditional bottle packs.

    • Adjustable AirStretch belt features ample stretch and chafe-free edging for comfort while maintaining bounce-free performance
    • Back-friendly symmetrical design eliminates uneven weighting, chafing and uncomfortable pressure points
    • AirFlow Mesh™ hybrid mesh technology wicks away moisture and circulates air between your back and the pack
    • 40 cu. in. compartment holds key, ID and cash
    • BPA-free 20 fl. oz. Hydraform™ water bottle nests laterally for a naturally comfortable fit
    • Low-profile bottle flattens center of gravity, reducing slosh and bounce
    • The Amphipod Full-Tilt AirStretch Velocity hydration waistpack securely holds its bottle in place and accommodates easy bottle access


    Item 813463

    Members: earn a
    $20 bonus card

    When you spend $100 April 14—29

    Single-use bonus card redeemable by
    REI members MAY 2—12, 2014.

    Not a member? Join Now!
    Add to Cart

    REI Membership

    Amphipod Full-Tilt AirStretch Velocity Hydration Waistpack - 20 fl. oz. Specs
    Best use
    0.65 liter
    40 cubic inches
    0.59 liter
    20 fluid ounces
    8.5 ounces
    0.24 kilograms
    21 - 48 inches
    1 main compartment
    10 x 5 x 3 inches
    Gear capacity (L)
    Gear capacity (cu. in.)
    Liquid capacity (L)
    Liquid capacity (fl. oz.)
    Weight - metric
    Fits waist/hips
    Pack access
    Number of exterior pockets

    Amphipod Full-Tilt AirStretch Velocity Hydration Waistpack - 20 fl. oz.

    Loading Ratings & Reviews...

    Amphipod Full-Tilt AirStretch Velocity Hydration Waistpack - 20 fl. rated3.1429out of5by7.
    Rated1out of5byfromIcicle buttBought this for long marathon training runs. Tried it out yesterday, in one degree cold. A half hour into the run I had (a) much less water than i'd expected, and (b) icicles all over my rear end. The bottle is chintzy, with a plastic valve that has no seal. As the thing is designed to sit horizontally across the lower back, it is pretty much inevitable that it is going to leak - and it does. I suspect, though I have not checked, that in addition to the $40 cost of this thing, a better quality bottle is available for purchase - one that doesn't leak all over your butt. The reason I haven't checked is that there is no chance I would pay more for what should be a no-brainer feature of a hydration pack. It shouldn't leak. Don't waste money on this. Headed back to REI today to return.
    Date published: 2014-03-01
    Rated4out of5byfromTakes some adjusting, but good packI purchased this mainly for the Pike's Peak Marathon. I also have a similarly designed Ultimate Direction hydration waistpack. The UD waistpack rubs a spot along my back waistline, so I thought I would try the Amphipod. I first wore the Amphipod in a 15 mile trailrace and my first impression was that it was difficult to tighten the waistbelt. The elastic belt makes it a little harder to get a snug fit and the the belt clasp isn't as easy to adjust. It took a fair bit of adjusting, but it eventually settled into the right spot. In comparison to the UD waistpack, the other thing I noticed was that the Amphipod doesn't have as much storage room for gels, bars, keys, phone, etc. I don't run with a lot of items, but if I'm on a trail running for 2+ hours, I normally bring along several gels. There is probably just enough room for 3 gels. I didn't have any issues with the bottle leaking. It is easy to remove and put back in the waistpack while running. Since the bottle removes from the right side of the pack, I'm not sure if a left handed runner would find it equally easy to remove? It has a little elastic type cord that slips over the mouthpiece of the bottle which holds it in place and keeps it from falling out of the pack. It might be nice to have one of these on both sides, so then the bottle could go in from the left or the right. Also, I appreciate the extra thought and design to the Amphipod bottle, it fits nicely in my hand. However, I'm not sure that it makes much difference in terms of comfort and how a regular water bottle would sit in a waistpack. All in all, I like the pack and will be using it on more runs. I have a pouch from another running belt that I've been able to slip on and I can keep it in the front with my phone and more gels when needed. The waistpack held up great during Pike's Peak and I did not have any trouble getting it adjusted.
    Date published: 2013-09-04
    Rated2out of5byfromWAY TOO BOUNCY! do not recommendMy friend has a previous incarnation of the amphipod full-tilt waistpack, and he loves it. This new version, though, thanks to AirStretch technology, is WAY, WAY, WAY TOO BOUNCY. I used mine today on a 5-mile trail run and it was torture when the bottle was full. No amount of cinching down the belt on my waist and around my belly fat and super-toned abs helped. I promptly returned it after my run (thanks, REI). Sad--I really wanted to like it, and the elastic pouch seemed to work well. I highly recommend AGAINST this product if you are doing any sort of running or jogging. (It's probably fine for walking.) The old version, without AirStretch technology (just woven nylon straps), is way less bouncy.
    Date published: 2013-08-17
    Rated2out of5byfromFor slower runners onlySo far I've used this waistpack for running 3 times on hilly trails and once on flat pavement. It is simply not suitable for running at paces faster than 8:00/km or 12:00/mi if your waist is narrower than your hips. In this case, the belt won't stay on the hips, it will move up to your waist while running and it will bounce widely - unless you tighten it enough (very difficult to do while running) but then it will compress your lungs, bowels and everything else in your abdomen. At a pace of 5:00/km it is only comfortable once the bottle is empty, so it might work for you if you start with a continuous steep climb, drink everything up by the time you start the descent, and finish with an empty bottle in your back. On the positive side, the belt is comfortable once adjusted for walking conditions. The bottle is sufficiently easy to drink from while running, it is very easy to refill and does not leave a bad taste. The belt's stretchy pocket can accommodate a large smartphone (Samsung Galaxy S3 without a case), an ID card and a tissue but not more. I would not recommend this product for thin people who see themselves more as runners than joggers. It should be very comfortable for short hikes (up to one or two hours, depending on temperature), and might be a good fit for slow jogging or for bulkier body types (not tested). I ended up happier running with the bottle in my hand, so instead I would recommend a handheld hydration set, which lets you carry the same amount of water and personal items.
    Date published: 2013-07-04
    Rated4out of5byfromHardly know you're carying itGreat for running. Does not bounce around and is secure. It can leak, but only if the valve is not seated completely. I can hardly tell I'm carrying it.
    Date published: 2013-06-12
    Rated4out of5byfromSo far, so goodI like the belt and bottle. It fits snugly in the small of back and has little bounce. The only minor drawback is that it's not super-smooth to access it if you're running hard on a trail (I don't run on roads...probably easier there) because of the need to have the little elastic loop over the valve to hold it in. Still, I knew that was a tradeoff going in for the benefit of it centered on the back. My biggest concern was that it would leak, being in there horizontally, but six pretty tough runs in and no leaks so far.
    Date published: 2013-04-21
    Rated5out of5byfromReally like this pack.Started running this summer in the southern US and quickly realized I needed to carry water. This pack has been great. The small zippered pouch fits an iTouch and my old flip phone, plus a key (warning: this doesn't stretch out the pack too much, but others have warned against over streatching pockets as zippers may fail. I haven't had any issues). While it may be minor, I hate hearing water sloshing around while I run and was worried that this bottle would be loud due to the sideways position. However, it doesn't. This makes for quiet, peaceful runs. It has a nice secure fit.
    Date published: 2012-09-15

    Ask a question and have it answered by REI product experts and fellow outdoor enthusiasts. Need immediate assistance? Use Live Help.

    Loading Questions & Answers...

    How are we doing? Give us feedback on this page.

    FREE SHIPPING With $50 minimum purchase

    MEMBERS, EARN A $20 BONUS CARD! When you spend $100 April 14-29. Single-use bonus card redeemable May 2-12. Details
    • Join REI today!
    • REI Membership
    • REI member benefits include an annual refund (typically 10% on eligible purchases).
    • Join REI today!
    • Sign up for REI Gearmail®
    • and get 15% off selected items!
    • Store Locator
    • Locate an REI store near you.
    • Find a Store
    © 2014 Recreational Equipment, Inc. All rights reserved. REI, the REI Tree and Mountain design, Novara, and
    REI Adventures are trademarks of Recreational Equipment, Inc.

    Find REI on: FacebookTwitterYouTubeFlickrMobile site