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  • Hydrapak - Ultraflask Collapsible Water Bottle - Malibu Blue
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  • Hydrapak - Ultraflask Collapsible Water Bottle - Malibu Blue

Hydrapak Ultraflask Collapsible Water Bottle

$18.95 - $20.95

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    • Malibu Blue, 500ml
    • Malibu Blue, 600ml

    9 Reviews


    Minimize water movement on your run.

    Your marathon is just three weeks away and you're hitting the peak of your training. So before you hit the pavement for that long run, grab the HydraPak Ultraflask Collapsible Water Bottle. Unlike traditional water bottles that remain bulky even when the water's gone, the Ultraflask shrinks as you drink to minimize sloshing and bulk. It comes with both a bite-valve cap and straw to fit your hydration preferences.

    • Soft water bottle for hikes, runs, and bike rides
    • Material is soft and flexible to shrink as you drink
    • Conforms to your hand or any pocket easy carrying
    • High-flow bite valve seals after every sip to stop drips
    • Includes removable drink tube for added convenience
    • Item #HPK0019

    Tech Specs

    thermoplastic polyurethane, silicone, HDPE
    300ml, 500ml, 600ml
    high-flow bite valve
    [300ml] 3.3x2.7in, [600ml] 6.5x2.7in
    Claimed Weight
    [300ml] 1.1oz, [600ml] 6.5x2.7in
    Recommended Use
    backpacking, casual, hiking, trail running, triathlon
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

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    UltraFlask 500 ML

    Part of theultra-light series, the 500 mL is so light, you might forget you brought it. Weighing in at just over an ounce, it’s optimal hydration, no matter what kind of runner you are. Its pliable material conforms to most pockets, it shrinks as you drink to minimize water movement and it can be used with or without the tube. Ultra light weight, ultra useful.

    UltraFlask 500 ML

    Ultraflask Collapsible Water Bottle

    The UltraFlask IT 500mL features our new IsoBound™ insulation technology that keeps water cold and won't sweat in warm temperatures. Engineered to keep fluids at an ideal temperature 38% longer than a standard reservoir. After all, cold water is more refreshing.

    Good Idea but...

    • Familiarity: I've used it once or twice and have initial impressions

    I really liked the idea of packable water bottles for traveling. However, I am not sure I would use these because they are so flimsy once you start drinking and they are not full. Maybe that is the idea but I think I will still with my Hydro.

    Would rather have a mini camelbak

    • Familiarity: I've put it through the wringer

    I like that this is pocket sized and the short (6") rubber hose nozzle that comes included. I can put the flask in an inner chest pocket, where it wont freeze on winter outings (e.g. backcountry skiing, climbing, etc), and the nozzle protrudes just far enough to reach my mouth when needed (if i unzip my jacket a bit to get at it).

    Two points for improvement: (1) the nozzle needs a way to be sealed (picture the nob used to seal a camel back hose). Otherwise it will drip if compressed (e.g. while stored inside a loaded pack). (2) the lid would be better in a side mount rather than top mount configuration to make it less bulky when stored in a pocket (again picture a camelbak, and think of how the lid is mounted for storage in a backpack inner pocket). Basically I just want a mini camelbak that I can store in a pocket on my jacket, but this is the closest you can get.

    Great for travel

    • Familiarity: I've used it once or twice and have initial impressions

    Fun squishy design. The bottle collapses down to almost nothing when empty. The lack of a rigid structure makes drinking a little awkward as you get closer to empty.

    Lightweight !

    • Familiarity: I've put it through the wringer

    Awesome lightweight bottle that collapses down to save space in your pack. I also really like the small size to stick in my coat while skiing to grab a swig of water on the lift. After its empty and collapsed you will hardly notice it is in your coat!

    Say no more to heavy water bottles!

    • Familiarity: I've used it several times

    Bought a few of the 600ml because they are great for long runs. No more being weighed down by heavy unused water bottles. Once you finished one of these just roll it up and pack it up.!