This is an original manufacturer-approved replacement part which is specially designed for use with Moen faucets. Its purpose is to filter out contaminants from the water. Over time it will wear out and may get clogged eventually requiring a replacement to ensure the best results. Refer to the owners manual of your model for the correct installation of this cartridge filter. Keep in mind it is sold as an individual component. Note, the filter includes two rubber o-rings to ensure a tight seal. The #14272 Cartridge Removal Tool is sold separately.