FITLY Soft Flasks

Size Guide

Ideal for quick drinks on the run. Gobble up a gel, wet a dry throat or re-hydrate. Designed to be used while running or biking.  Store directly in your front, side or back pockets. FITLY Flasks shrink as you drink so nothing ever moves, bounces or rattles.


  • No liquid bounce - Soft bite to quick flow
  • Shrinks as you drink
  • Leak resistant and rigid cap ring for easy refill
  • Light, durable, built to last - 100% BPA & PVC free
  • Ideal to drink on the go

    4 models to choose from:

    FLASK150 (5 oz): small enough to fit in FITLY's SUB45 front pockets for quick access.

    FLASK250 (8.5 oz): a compromise between size and volume.

    FLASK400 (13.5 oz): go a little farther., take a little more.

    FLASK500 (17 oz): an ingeniously low profile design to use as a standalone soft flask (screw-on mouthpiece included) or with the 23 in (58 cm) tube, 45 degrees angled rotating mouthpiece with a flow-stop, and minimalist tube attachment.

    Important: FLASK500 is not made to be used with SUB45.

    COMBO = 1 FLASK150 - 1 FLASK250 - 1 FLASK400

    How to use

    Softly bite the mouthpiece - press the flask - suck on the goodness!

    The more you press, the faster the liquid will exit. The walls collapse as you drink letting you absorb almost 100% of its content.


    Quick note: avoid mixing any liquid container with electronics.

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