To benefit as long as possible from your drinking system, the mouthpiece should be replaced from time to time. The soft bite valves are made of durable silicone. A perfect accessory for users who bite the valve while drinking, or to pack in an emergency kit along with a band-aid and a small roll of Duct Tap. Mouthpiece consisting of a sleeve and valve, suitable for replacing all bite valves on HydraPak's 2023 Reservoirs and tubes featuring the Comet Bite Valve