1 Filter Cleans 50 Gallon - Over 88 pitchers of great tasting water; Reduces chlorine taste and odor * Tested and Certified by NSF-Reduces up to 53 contaminants including Mercury, Cysts (cryptosporidium & giardia), Lead and Asbestos * Solid Block Carbon is more effective at reducing impurities * Easy and Quick To Install * Fits All CWS100A, CWS100A2, CWS100B, CWS100B2 and CWS100AW