The Quick Stow Flask Bite Valve by Camelbak is a replacement accessory that allows you to change a valve that no longer functions or has a defect on your Quick Stow flasks. Its silicone design ensures a good hydration flow. The Quick Stow Flask Bite Valve closes automatically once you release the pressure, ensuring perfect sealing. Guaranteed BPA, BPS, and BPF free, this valve will have no impact on your health.