Bite valve cover with integrated tether Compatible with Gregory's DryLock Magnetic Bite Valve Thread tether over hose before bite valve to secure cover Fits up to a 0.5" / 13mm outer diameter hose Bite valve cover with integrated tether to keep your next adventure dirt and dust free (at least in your reservoir). Compatible with all of Gregory's Dry lock Magnetic Bite Valves and reservoirs. Simply thread the tether over the hose to secure and you’re ready to hit the trail.