The K&H Thermo©\Kitty Bed has a dual thermostat heating unit buried deep within its thick, super soft, orthopedic foam base. It warms the surface 10©\15 degrees above ambient air temperature to your cat"s normal body temperature when in use. The washable cover comes in two colors and is attractive in any room in the house. Indoor use only. One year limited warranty. Features: Recommended for indoor use. Uses only 4 watts. 16" diameter. Available in 2 colors. MET Listed. 1 year warranty. Sleeping Dimensions: Small: 15" x 15". Large: 19" x 19".