Approved for use either indoors or outdoors, Allied Precision's Heated Pet Mats are constructed of durable, weather-resistant plastic with welded seams for safety and longer life. This mat includes a machine washable fleece cover. Allied Precision's unique, patented design allows air flow completely around the heating element to eliminate "hot spots" common with other plastic mats. These mats are designed to be used in dog houses, garages, kennels, or anywhere your pet needs added warmth. Small: 13x19 60WMedium: 17x24 70WLarge: 24x29 100W | Allied Precision Heated Dog Mat in Black | Size Large