No-Draft™ technology provides efficient air cleaning without cool air exhaust draft. Features two filtration systems; a true HEPA™ filter, removing 99.97% of airborne particles as small as 0.3 microns, and an activated carbon pre-filter, to diminish common household odors. Intelli-Check™ filter change indicator. Includes two non-permanent HEPA™ filters and one activated carbon pre-filter. Three speeds. Air Cleaner Machine Type: HEPA; CADR: 150; Maximum Room Size (Square Footage): 225 sq. ft.; Maximum Room Size: 15 ft. x 15 ft. Manufacturer's limited five-year warranty.