. . . "Q & A KDF/GACPLUS Coconut Shell GAC Cartridge with KDFThis cartridge contains a patented media, KDF (U.S. Patent 4,642,192) which has been tested to have bacteriostatic properties in addition to effectively removing Chlorine, Lead, Arsenic, Cadmium and other contaminants that may be present in the water.This cartridge should be installed with the gasket end against the screw cap." . . .