Hunter's HEPAtech Air Purifiers feature a Whisper-Quiet Fan that draws air into the unit without excessive noise. An advanced activated carbon prefilter reduces cooking, tobacco and pet odors while also capturing larger dust particles, lint and pet hair from dirty air. A permanently charged HEPAtech electret filter effectively captures 99.97% of all airborne particles as small as 0.1 microns in size that pass through the filter. An ionizer distributes negative ions througout the room to enhance the cleaning process while freshening the air. Effective airflow design exhausts clean, purified air back into the room from the top of the unit to avoid stirring up settled particles. Hunter's space-saving slimline styling fits flush against the wall, so units don't encroach on living areas or interfere with household activities.