The Platypus Universal Bottle Adapter allows the connection and backflushing of all GravityWorks™ systems with just about any drink bottle made. Filter directly into a wide range of hard bottles and hydration systems, eliminating the weight of a dedicated Clean Reservoir. Its multi-component design lets you take just the parts you need for your vessel of choice to further lighten your load. Works with GravityWorks™ 4 oz. Complete Kit (Campmor sku # 84072) and GravityWorks™ 2 L System Bottle Kit (Campmor Sku # 84071) Wt. 2 oz.