Enhance the air quality in any room with the Holmes 2.5 Gallon Ultrasonic Humidifier Model HM-550. This powerful and glossy white humidifier operates silently with an operating sound rating of only 10 dB. With adjustable humidity control and a built-in humidistat, this unit is perfect for large recommended room sizes of up to 120 sq ft. Featuring automatic shut off and ultrasonic humidification technology, this electrical humidifier is perfect for any room in the house. The tank capacity of 2.5 gal (9.5 L) ensures long-lasting use without frequent refills. This Holmes humidifier weighs only 3 lb and measures 12 in in height, 18 in in width, and 10 in in depth, making it easy to move around as needed.