This is an offer for one Aqua-Pure AP-250R replacement water filter (Aqua-Pure is a division of CUNO, one of the world's leading water filter manufacturers). This filter fits the Aqua-Pure AP-DWS250 undersink drinking water system. These filters provide sediment, chlorine taste and odor reduction, producing refreshing, great tasting drinking water. These filters are easy to change -- no tools required, no sump wrench and no messy spills.