H2O SURVIVAL(tm Water Filter Straw Adaptor for the Travel MAX or H2OLIFEGUARD Water Filter Straw WATER FILTER STRAW SLIDE-ON ADAPTOR- Allows you to attach the H2O Survival Water Filter Travel Straw MAX or H2OLIFEGUARD to any COKE, Seltzer Bottle and most Standard water bottles and many Hydration Bags. WATER FILTER PURIFIER ADAPTOR easily allows you to SOURCE & STORE- Water from any water source and store in our hydration bag or your favorite container with Coke bottle sized threads. SIMPLY SLIDE IT ON-With a simple twist and slide-on or off motion. Adaptor fits snugly to the end of your Straw and is easy to remove. EXTEND YOUR REACH- The NIPPLE on the end of adaptor allows for attachment of a 3/8 line to hard to access water. Like if you are in a boat or trying to access water off of tall rocks etc. EXCLUSIVE USE -For our H2O SURVIVAL Water filter Travel MAX & H2OLIFEGUARD Water Filter Straw Models only.