Katadyn KFT Expedition Water Filter (Worlds BEST Water Filter)1 Filter included with the system* Additional filters are sold separately! The Katadyn Expedition Water Filter is perfect for a group on the move that needs a water source it can count on. Its high performance filtration uses silver impregnated ceramic to ensure the water is free of bacteria. As easy to use as it is to pack along and as indestructible as it gets. Efficient, long lasting, durable filtration Eliminates bacteria, protozoa, cysts, algae,