Honeywell Premium Replacement Humidifier Filter - Holmes F - Model HC-28-TGT - Fits Holmes HM1200 Air Washing Layer Helps Capture Large Particles From The Air That Passes Through The Filter Filter Helps Remove Minerals & Pollutants From The Water In The Humidifier Protec Antimicrobially Treated Filter Inhibits Up To 99.99% Of The Growth & Migration Of Mold, Algae & Bacteria On The Filter