This professional quality Optima diffuser (110v - uses no heat) is one of our most versatile. The Optima 807 Model has the capacity to diffuse oil into a large area such as a shop or office of up to 900 square feet or to fragrance a smaller room (200 sq. ft.) in minutes. The Optima can be run a full capacity or be turned down to a very quiet level. Use with ONLY therapeutic grade essential oils like our SomaTherapy brand. The pump is dark blue and about 7 x 4 x 3 inches in size. For more versatile use, this diffuser can be purchased with a programmable timer.