A replacement cartridge for the Katadyn Hiker Pro Microfilter. Also fits Katadyn's Hiker and Base Camp microfilters. Pleated filter has over 129 sq. in. of filtering surface. Pore size of .3 microns filters out bacteria, protozoan cysts (such as Giardia and Cryptosporidium) and particles. Carbon core removes unpleasant tastes and odors. Filters up to 200 gallons (800 liters).