Spend more time in camp relaxing, let gravity filter the water. The Katadyn Gravity 6L effortlessly removes bacteria and cysts such as Giardia and Cryptosporidium at an output of up to 2 liters per minute. Simply fill the six liter bag with the cleanest water source available. Clip the buckle closure and hang the bag above your water container. The Ultra Flow Filter(TM), with its 0.2 micron (0.0002 mm) pleated glass fiber element reliably filters bacteria, cysts and sediment. A cleanable filter protector lengthens the lifetime of the filter element so it can clean up to 400 gallons (1500 liters) of water. A clear window in the bag lets you see when it's time to refill. The outlet hose can be removed with a quick-release valve equipped with auto shut off. That keeps the hose from coming in contact with contaminated water during refilling. The shower adapter (Item # 70864.01, sold separately), converts the bag into a refreshing outdoor shower. There's a one-year AntiClog(TM) Guarantee on the filter element. Katadyn warrants your Ultra Flow Filter Element to be free from defects that cause the filter to clog. Great for family and group camping water purification.