Honeywell HAC-700PDQ Replacement Filter for Honeywell and Duracraft Natural Cool Moisture Humidfiers Type: Replacement Filter Used For: Humidifier Feature: Air washhing layer helps capture dirt, dust and pollen Two 3 piece inners Filter helps remove minerals and pollutants from the water Protec treated filter inhibits up to 99.99% of black mold growth on the filter Note: HCM-750 requires two filters to operate properly