This Pentek FloPlus-20 Filter is a 20 inch carbon block water filter replacement cartridge for use in many water filter systems. The Pentek FloPlus20 is a standard diameter filter (2 1/2 diameter) that maintains a high flow rate despite its very low 0.5 micron rating. The Pentek FloPlus-20 is made specifically for applications where a low pressure drop combined with depth filtration is needed. Able to withstand a maximum temperature of up to 180 degrees Fahrenheit it can also be used in high temperature applications. This advanced Pentek water filter replacement cartridge is specifically made to reduce the bad taste and odor of chlorine and other chemicals in water. It is a dual purpose water filter cartridge in that it also removes and reduces sediment dirt rust sand silt limescale and other common particulates. Additionally the FloPlus20 removes 99.95% of harmful cysts such as cryptosporidium and giardia. This filter has been tested and certified by NSF International to NSF / ANSI Standard 53 for the reduction of cysts.