The CamelBak Crux(TM) reservoir on/off valve pairs with the Big Bite valve, shutting off the water flow for added security during transport. Please note: this On/Off Valve does not ship with a Big Valve and it is NOT compatible with older style AntidoteA(R)or OMEGAA(R); reservoirs. Features Ergonomic on/off valve make it easy to grip tube and toggle while you&';re on the move Turn off water flow from CamelBakA(R) Crux(TM) Reservoir during transport 45-degree bend perfectly positions the Big Bite(TM) Valve for easy drinking The patented Big Bite(TM) Valve mouthpiece offers Hands-Free Hydration and is ideal for any high-performance situations. Self-seals after each drink to eliminate annoying drips. Specifications BPA/BPS/BPF Free true Dimensions 6 cm / 2.5 in long Material Polypropylene/ LDPE (on/off valve)