3-Stage Filtration: The True HEPA Filter, Pre-Filter, and Activated Carbon Filter work together to trap dust, smoke, odors, and other airborne contaminants.High-Efficiency: The 360-degree design filters up to 40 percent more air per hour than other purifiers, capturing 99.97 percent of airborne contaminants as small as 0.3 microns in the process.Sleep Mode: Filters the air as quietly as 25dB at the lowest level for a restful and soothing indoor environment, helping you sleep deeply.Auto Mode: The intelligent sensor evaluates air quality and adjusts fan speeds in real time to maintain healthy standards.Wide Coverage: Enjoy fresh air in only 30 minutes in rooms as large as 881 sq. ft. or 82 sq. m. and 18 minutes in rooms as large as 538 sq. ft or 50 sq. m.Every Levoit product comes with a 1-year warranty and a lifetime of customer support. Register your device online at Levoit to extend your warranty by an additional year.