Bunn MPN 30331.1004 REPLACEMENT CARTRIDGE.Designed for one or two .5 gallon (1.9 litre) coffee brewers. They also work well with a BUNN HW2 hot water machine. Provides 1,500 gallons (5,678.1 litres) of superior sediment, taste/odor and chlorine reduction @ .5 gpm. 5 micron graded density filtration for long life. Perfectly sized to ensure quality coffee and long-term performance of 1 to 5 pot brewers (up to 15 lbs. (6.8 Kg) of coffee/week). Special scale inhibitor provides six months of scale reduction and guards against corrosion. Limited supply. UPC 072504052892