4-stage H13 True HEPA filtration effectively removes at least 99.95% of particles as small as 0.1 microns, including allergens, such as pollen, dust, pet dander and smoke in rooms 300–550 square feet. Antimicrobial HEPA treatment applied to the True HEPA filter inhibits the growth of odor and stain-causing microorganisms to extend the filter lifespan. Monitors occupancy and air quality with EnviroSmart™ Technology. PureView ™ Technology shows the percentage of particles captured and a live status of room air quality. Designed and engineered for long term use backed with 5-year warranty.