The Purification on Demand Multi-Use Purification System has an innovative design that meets a variety of needs. It can be used as a lightweight emergency straw, hydration pack attachment, gravity filter, or attached to a 28mm bottle. This system includes the POD cartridge, silicone straw, bite valve, bite valve cover, POD housing, and a 1.5L soft bottle. The filter lifespan is 50 gallons.