Pentek EPM-20BB # 155783 EPM20BB Big Blue Carbon Block Replacement Water Filter Cartridge Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. Big Blue 10 Micron Carbon Block Water Filter. 20" long X 4 1/2" diameter. 6 per case, sold individually. Ametek # 155783 EPM Series cartridges are a modified version of our "EP Series" cartridge. An economical price makes this cartridge suitable for taste, odor and chlorine reduction, as well as sediment filtration. EPM Series cartridges are manufactured using a patented process that yields a cartridge with a nominal 10 micron filtration rating, high porosity and greater chlorine removal capacity. The high porosity design helps prevent the cartridge from plugging before its adsorption capability is exhausted, maximizing the utilization of the carbon while maintaining low pressure drop. Order a case and save even more.