WW0002166, Watts, Carbon Block Replacement Cartridge For Full Flow Housing

This black replacement carbon block is designed for the 4 GPM OneFlow (R) cold water single cartridge style filter system. It is NSF and ANSI certified for material safety and should be replaced every 12 months by isolating the tank with a bypass valve. Carbon replacement filter cartridges are not warranted to perform for any period of time because the service life of replacement carbon filter cartridges varies significantly with local water conditions and volume.