... -particulate contaminants,sludge&rust.2nd Layer Ion Exchange Rensins Content:US NSF ANSI/NSF -44- approved Ion Exchange Resins Functions ... NSF 42) Functions:Inhibits harmful bacteria growth Performs secondary adsorption of chlorine,unpleasant odours,colours and toxin substances8th Layer Magnetic Stones ... Water Quality , FDA&EPA, Fresenius, CICS,SGS,KDF,etc. 5 patents 11 certifications 220V Water filter