This ultra lightweight filter uses a hollow fiber membrane that physically removes particles, protozoa, and bacteria down to 0.1 micron in size, including giardia, salmonella and cryptosporidium. The compact and durable filter can effectively treat water directly from a lake, your hydration pack or a household faucet. Includes hollow fiber filter, faucet adapter, hydration pack assembly kit, cleaning and maintenance instructions. Maintain a fast flow of water by back washing from a household faucet. Measures 6" x 1½"Dia. Weighs .50 lbs.