This simulated flame colorful light can be used to create a romantic relaxing and soothing atmosphere. The crystal salt stone release the negative ions to help you breathe the fresh fragrance which is product by putting essential oil into the water. It has an automatically power off when the water compartment empty and the timer set are 1/3/6 hours. The low noise level is ≤36db making it virtually noiseless so it will not disturb you when sleep or work at the desk. It automatically changes color when it is on. It is powered using the USB cord and has a touch on and off switch. It is made with high-quality ABS and PP material. It can be used at home or in the office.