Westinghouse WDD100 Ultrasonic Humidifier with Aromatherapy, 8-1/2-Ounce Tank Combination aromatherapy diffuser and humidifier for rooms up to 400 square feet Continuous and interval programming perfect for distributing the appropriate amount of aroma Multi-color lights add to the calming effect Runs for 24 hours per filling of 8-1/2-ounce tank; sample Elixir included Measures 5.2 inches wide by 5.2 inches deep by 9.4 inches high; 1-year limited warranty