The Nathan 20 oz Soft Flask with Bite Top makes it easy to bring your water on your run. The soft-sided flask fits easily into the pocket of a vest, and the 20oz capacity is enough on its own for a quick outing or increases the amount you can carry with a bladder. Nathan added an easy-to-use Bite Top for quick sips and drip-free performance. Perfectly compatible with all Nathan hydration vests, the 20 oz Soft Flask is the simple solution to carrying your water.