Operates quietly to help reduce up to 99.97% of airborne allergens such as pollen, dust, mold, pet dander and smoke to provide relief from irritants in the air. Pre-filter captures larger particles and true HEPA filtration captures and traps particles as small as 0.3 microns from air passing through the filter, so you can breathe comfortably. Includes one aer1 filter featuring the odor eliminating power of Arm & Hammer baking soda.