Fill your space with the scents you love with the 90 ml Ultrasonic Aroma Diffuser. This Diffuser runs up to 4-hours continuously or up to 8-hours intermittently. Customize your relaxation with the 60, 90, 120-minute timer and 7 LED lights. The 7 LED lights can rotate or be fixed to one color. To use, add water and the essential oil of your choice, turn it on, and let the cool mist refresh your mind and body. Add more drops to increase fragrance intensity.