The Ultra3 Vornado Ultrasonic Humidifier is a uniquely effective means to create a comfortable, perfectly humidified living space. Vornado's deep pitched blades pull large volumes of harsh, dry air through the unit and then, using Vornado's signature Vortex Action, circulate the humidified air throughout the room, providing complete and uniform humidification. This unit has a built-in humidistat to automatically regulate moisture output or can be set to run continuously. The easy-to-use push-button controls with LED lights provide easy visibility of current settings. Three fan settings are available - High, Low, or Auto. In the Auto setting, the fan and transducer will fluctuate up or down to maintain the set humidity level. With a coverage area up to 600 sq. ft., the Ultra3 has you covered, no matter the season.