Whirlpool WHKF-DB1 Undersink Water Filter Compatible Cartridges 3 Pack. The carbon block cartridge is an ideal cartridge for chlorine / chemical reduction for point of use drinking water and reverse osmosis systems. It also has a dirt / sediment rating of 0.5 micron nominal. The extruded carbon block design will ensure that this cartridge will perform optimally for 6-10 months before being exhausted. The coconut shell carbon provides impressive absorbative capacity ideally suited for water purification. A great and more affordable alternative to: Sears/Kenmore 34370, Watts PWCB10S, Pentek CBC-10, Omni GAC1-SS, KX Industries USA 32-250-125-975; 32-250-10-GREEN; 01-250-10-GREEN; 01-250-125-975. The double open ended (DOE) cartridge configuration has an industry standard 2.5 inch x 9.75 inch dimension. It efficiently reduces chlorine/chloramines, VOCs, pesticides and taste / odor contaminants. The cartridge should be changed every 6-10 months or upon substantial pressure reduction.**Please note this is a compatible spare part and the manufacturers' names, photos and part numbers have been used for reference purposes only.