The Honeywell HEPA-Type filter’s efficiency is rated at 95% in capturing airborne particles such as smoke, dust, pollen, cat dander and mold spores*. A washable pre-filter captures large particles. The air purifier operates quietly while changing the air in the room. The Electronic Filter Clean Indicator illuminates to remind you when to clean the filters.For extra air freshening, there's an ionizer which can be turned on or off as desired. Recommended for medium size rooms, the slim tower design and quiet operation makes it ideal for any room in your home.