Sawyer SP121 Just Drink Inline Water FilterSawyer SP121 Just Drink Inline Water FilterThis filter accessory allows you to connect your inline filter to most water taps. The adapter head is made of flexible PVC which allows connecting to different size faucet mounts. Great for traveling, camping, or for emergency situations when youó»re not sure if the water is safe to drink. 1 Million Gallons Guaranteed. We are confident in our million gallon claim because you can continually clean the filter by back washing it with clean water. So there really is no end to its useful life. That is why we can GUARANTEE THE FILTER FOR LIFE as long as you follow the simple care and use instructions. Back washing is not required often unless you are filtering very turbid water. Back washing only takes a few seconds. If you are accustomed to a ceramic filter, the leaning ratio is approximately 0:1. In other words, by the 20th time you would have cleaned your ceramic filter, it would be time to back wash this filter for the first time. NO REPLACEMENT FILTERS OR CARTRIDGES ARE NECESSARY. We trust you will thoroughly enjoy the ease and extra protection this proven next generation technology offers you. The Sawyer Water Filters feature a 0.1 Micron Absolute Hollow Fiber Membrane which uses medical technology developed from kidney dialysis. When the water is drawn through the filter it flows through the side walls of the Hollow Fiber tubes. Sediment, bacteria, protozoa, cysts, and other contaminants are filtered out exceeding all applicable EPA recommendations. No Pumping, No Chemicals, No Waiting and No Worries.