This unique aromatherapy diffuser is wonderful for both adding humidity to the air and dispersing your desired scent of essential oil to enhance your room's atmosphere. The ultrasonic transducer transforms water and essential oil into a cool mist. This diffuser also includes output adjustment buttons for a low or high mist, a safe auto off feature when the water runs out, and a whisper quiet operating system so it can be used both at night and during the day. It also offers a lighting feature to create a relaxing mood. 5.9” W x 5.1” H Features: • Unique Shape Design • Attractive Black Ceramic exterior • Operates 3-4 hours • Holds up to 3.38 fl. oz. (100 mL) of water • Three Auto changing LED colors (optional) • Offers 4 operational settings • Perfect for any room • Fill base with tap or filtered water, add 1 - 2 drops of essential oil if desired. Never pour water into the opening of Air Vent.