Honeywell True HEPA air purifier with germ reduction. QuietCare technology provides quiet HEPA operation. The True HEPA filter removes at least 99.97% of common household particles as small as 0.3 microns from the air passing through it such as dust， pollen， tobacco smoke， and cat dander. Reduces airborne germs， bacteria， mold spores， and fungus with up to 100% efficiency. The carbon pre-filter captures larger airborne particles and helps remove common household odors. Air is circulated up to 5 times per hour. Also features electronic filter indicator which reminds you when to replace the filters. This model is recommended for medium size rooms. Equipped with easy tap electronic controls. 3 air cleaning levels plus Turbo Clean setting and a 2， 4， and 8 hour timer. SurroundSeal technology helps minimize air leaks and insures that the air passes through the filter capturing particles. AHRM certified. AHAM CADR (smoke): 200. Requires both the filter and carbon pre-filter to operate.