Put the UltraSignup Soft Flask 500mL/17oz into a compatible running pack and enjoy convenient hydration on the run. It can also be used independently of a hydration pack as a handheld water bottle by looping the attached string around your wrist. The soft flask uses safe and reliable BPA-free materials in a small, collapsible design that shrinks as you go to eliminate any water sloshing and keep you focused on the run ahead. With its wide opening, you can quickly and easily fill the Soft Flask, while a high-flow valve releases fluid faster to keep you hydrated without any fuss.

This bottle is 500ml and is 9.5″” x 3.5″” when inflated.