The Essential Oil Diffuser works by using slight vibrations to emit a fine mist of cool water carrying your favorite essential oil. All Airome products are made using quality materials of ceramic, porcelain, glass, and metal. The diffuser allows you to enjoy a mist of essential oils for up to 8 hours. From traditional and classic to modern and geometric, we've created a variety of styles for every mood and decor. Your choice of two settings of intermittent, which will run for 8 hours, or continuous, which runs for 4 hours. Diffuser automatically shuts off when water runs out.