The SilentComfort True HEPA air purifier removes up to 99.97% of common household particles as small as 0.3 microns from the air passing through it such as smoke, dust, pollen, mold spores, and pet dander. The carbon pre-filter helps remove odors and captures larger particles, while helping to extend the life of the HEPA filter. This air purifier also features SilentComfort advanced airflow design for ultra quiet high speed operation. The No Draft Technology feature provides air cleaning without a cool exhaust draft and the Intelli-Check filter monitor reminds you when to replace the filters. Recommended for medium to large rooms. SurroundSeal Technology helps minimize air leaks and insure that the air passes through the filter, capturing particles AHAM Certified Made in the USA