Designed, assembled, tested, and supported in the USA. H2EO AIRCARE ULTRASONIC DIFFUSERS OFFER THE ULTIMATE IN SAFE, EFFICIENT, COMPLETE DIFFUSION OF ESSENTIAL OILS INTO A MEDIUM TO LARGE ROOM. They use safe, low voltage direct current to harness the science of ultrasound. Subject to factors including air turnover and humidity, 1500 to 2200 cubic feet can be effectively covered. Using the water in the bowl of the diffuser as the "carrier" for the essential oil, each nano-droplet of water is covered with a molecule-thin coating of essential oil, which rapidly becomes part of the room's atmosphere. * An H2EO diffuser weighs less than one pound and is approximately 4" high and 7" in diameter. * The energy-efficient switch-mode power adapter included weighs less than 5 ounces. * Colored lights options set the mood. * Display lights can be turned off for sleep while diffusion continues at the volume level you have chosen. When the water level gets low, the diffuser shuts itself off. * Backed by a full one-year warranty, and friendly, personal, after-sale service and accessories. * H2EO's Multi-Colored Lights Diffuser offers you four display lights options: 1) blue lights; 2) green lights; 3) red lights; 4) a color-changing sequence; or 5) all display lights turned off (while still diffusing).