Replacement straws and bite valves make your Eddy water bottle work like new. Big Bite Valve's one-piece, silicone design self-seals to prevent leaks. Two replacement straws enable sipping without tipping. CamelBak Got Your Bak Guarantee: If we built it, we'll Bak it with our lifetime guarantee. Materials: Medical-grade Silicone, Low Density Polyethylene.