HeatTrak HRT11-36 Industrial Snow-Melting Stair Mat, 11-Inch by 36-Inch, 120 Volt (Discontinued by Manufacturer) Industrial snow-melting stair mat; measures 11 x 36 inches Requires 120-volt power unit (sold separately) Built with reinforced SBR rubber and designed to be left outside for the entire winter season Melts 2 inches of snow per hour Can connect to additional Industrial stair mats to form a set