Ultraviolet light technology provides up to 99.9% germ-free humidification, kills bacteria mold and spores. Quietcare technology makes this unit 30% more quiet than others. 3 moisture settings and adjustable humidity control. Slim tower design. Runs up to 24 hours per filling. For use in rooms up to 1050 sq. ft. Use with antimicrobial filter Model No. HAC-504AW (SKU 500817) and ProTec cleaning cartridge Model No. PC-2 (SKU 501031).