The Katadyn Siphon turns any water container into a gravity-fed microfiltration system. Simply place the ceramic filter (hose attached) into the container, place the container on higher ground, and let the siphon action take care of the rest. That's it! Filters 1.2 gallons/hour. The Siphon is a member of Katadyn's exclusive Endurance Series, which basically means this filter will last forever. Its silver impregnated, cleanable ceramic element will clean up to 5,000 gallons of water. The Siphon also works as a replacement element for the Katadyn Camp system.