PureGuardian Humidifier 2-Gal. 120-Hour Ultrasonic Warm and Cool Mist Humidifier with Aromatherapy * Large 2 gal. tank provides up to 120-hours of run time and is great for medium to large rooms * Ultrasonic technology quietly disperses a fine mist providing relief from the dry air * Silver clean protection fights the growth of mold and mildew on the surface of the water tank * You choose warm or cool mist to optimize your comfort * Electronic control options include night light, 12-hour timer and 3-speed settings * No evaporating pads or wicks to clean or replace * Directional nozzle broadens mist in 2-directions throughout the room * Low water indicator illuminates when it's time to refill the tank * Auto shut-off * Model # 969521