The Honeywell Replacement Wicking Filter A, 1PK, helps remove minerals & pollutants from the water and reduce white dust. The Protec Antimicrobial Treatment Filter helps prevent the growth and migration of mold, algae & bacteria on the filter. It inhibits up to 99.99 percent of mold growth. The Blue Air Wash layer removes large particles from the air and provides additional structural support. 1) Optimized design maximizes moisture output, 2) For use with Honeywell models: HEV355, HCM-350, HCM-710, HEV312, HCM-315T, HCM-300T.