Protec antimicrobial treatment inhibits up to 99.99% of black mold growth and prevents the growth and migration of mold, fungus, and other bacteria. Removes minerals and pollutants from water. Air washing layer helps capture dirt, dust, and pollen. Fits Honeywell model No. HCM-1000 and 2000 series, HCM-500 series, ECM-250i, HCM-600 series, HCM-300T, HCM-315T, and 63-1508.