Vicks Ultrasonic Humidifier with Variable Mist Control allows you to adjust the humidity in your room; Directional mist outlet allows you to adjust the direction and intensity of the mist; Quiet Almost Silent operation; Operates up to 20 hours per filling; Comes with Demineralizing cartridge to reduce white dust; Large Tank Opening for easy cleaning; 1.7 gallon output per day; Best for Medium to Large Rooms.