The Supernova Ultrasonic Diffuser runs up to seven hours continuously or 14 hours intermittenly. Customize your experience with the 60, 90 or 120-minute timer and seven LED lights. The led lights can rotate or be fixed to one color. All you have to do is add water and the essential oil of your choice to fill your room with the scents you love. A cool mist is released to provide the aromatherapy benefits to relax and restore.