Product Detail 24 gauge cold rolled steel construction Three-stage filtration: prefilter, HEPA filter, V.O.C. filter Effectively cleans air in rooms up to 50 sq. ft. Thermally protected Class "B" insulated motor Designed for continuous operation . The "Amaircare 2500 HEPA Air Purifier Sandstone" is best product for you. We recommended Amaircare 2500 HEPA Air Purifier Sandstone