This Honeywell HDC200 replacement demineralization cartridge helps filter out minerals & other impurities from the water that cause "white dust".
Recommended Replacement: Every 20-30 fillings depending on water quality, or when humidifier has not been run for an extended period
Honeywell: HUT-200, HUT-200B, HUT200, HUT200B
Other Manufacturer Part Numbers: UHONEYWELLHDC200O