USWE Ultraflask 600

The ultimate high performance bottle, designed to give quick access to hydration when running, biking, skiing and every sport in-between. Lightweight, flexible, and easy to carry the ULTRAFLASK collapses as you drink. This eliminates sloshing and allows you to pack the empty flask tightly away. The patented, spill-proof, self-sealing, bite-valve generates an exceptional water flow and is easy to remove for cleaning.