Replacement Model-3M Filtrete 3US-AF01, 3US-AS01, 3M AP3-765S, 3M AP3-C765, AP Easy C-CS-FF, WHCF-SRC, WHCF-SUFC, WHCF-SUF Filter Cartridge; Fits 3US-AS01 Advanced Under-Sink Filtration Systems, AP Easy CS-FF Under-Sink Filtration Systems.