The Nathan ExoShot Flask is a uniquely shaped soft flask that comes complete with a locking cap and bite valve to keep your hydration from spilling. This patented system fits all Nathan race vest pockets. Taste-free technology will allow you to enjoy the taste of your hydration and not the bottle. It works great as a hand-held or with a vest. ExoSpine provides structure. Dishwasher safe on the top rack. BPA-free bottle.