Vornado Ultra1 Whole Room Ultrasonic Humidifier Humidifies up to 900 sq. ft. through the use of vortex circulation Electronic humidistat for automatic humidity control and 2 fan settings (low, high) Push-button controls with LCD screen for easy confirmation of settings 2 gallon tank capacity and up to 3.5 gallon output every 24 hours Backed by a 5-year limited warranty Refer user manual below.