Plastic LOW NOISE & SLEEP BETTER -- Ultrasonic diffusers generate the vapor without any heat, which best preserves the integrity of the essential oil. You can combine two or more essential oils to create a unique blend. You barely notice the tiny bit of white noise, which may help you relax and sleep better but not obnoxious. It operates quietly without water dripping, creating a restful and soothing environment for undisturbed relaxation, reading, learning, working, and sleeping. ELEGANT LOOKING & LARGE CAPACITY -- The aromatherapy essential oil diffuser is made of plastic with a faux wood look and modern design, it blends naturally with most home decor. The changeable colored lights bring an elegant view, create a relaxing atmosphere to the room, and make your life more colorful.