Air purifier with near silent operation is ideal for rooms up to 580 square feet at five air changes per hour. It utilizes SurroundAir™ which allows clean air to be released out of three sides instead of one. It is 99.97% efficient for particles down to 0.1 micron in size, and is made of a superior all steel construction. Energy Star certified purifier features three speeds and filter change indicator. Measures 28 4/10" H x 23 6/10" W x 15 7/10" D. Five-year warranty. UL listed. Model # 503.