Granular Activated Carbon Filter Cartridge:Using NSF certified granular activated carbon as material, the Activated Carbon Filter Cartridge is good at removing objectionable tastes,Chlorine,unpleasant odor,spore,lead and microorganisms. The activated carbon the filter cartridge used has been processed by acid-washing and wind-selection and the end caps are fixed with special PP layer instead of general non-woven cloth. So no carbon fines releasing from the filter cartridge, at the same time, it keeps a high flow.