FITS RUNNING BELTS AND VEST POCKETS: Low profile soft flask and minimal cap design are specifically built to fit snugger pockets in running belts and vests. DESIGNED FOR COMFORT: The tapered shape with a pinch-welded bottom and smaller cap size makes it easy to carry, preventing any pokes or irritation during activity. COLLAPSIBLE FLASK: Soft material conforms to pockets, and shrinks as you drink to reduce movement and pack away easily when empty. SPILL PROOF LOCKING CAP: 28mm locking cap easily opens and closes with a touch of the thumb, preventing leaks and drips. BEYOND LIFETIME WARRANTY: If you experience any issue, we’ll repair or replace the item for free. Whatever it takes to keep your adventure going.