About this itemThis genuine Levoit Air Purifier Filter replacement for the Levoit Aerone True HEPA Air Purifier employs a three-stage filtration including Fine Preliminary, True HEPA and Activated Carbon filters to remove 99. 97% of dust, allergens, bacteria and odors. To do its best work, Levoit recommends replacing the filter every 6-8 months - the filter may need to be replaced sooner or later depending on the air quality in your area. Features