HeatTrak HCM30-48P 120-volt Carpeted Snow-Melting Door Mat, 30 by 48-Inch Snow-melting door mat; measures 30 x 48 Inch Chevron carpet surface provides your home with the look of a stylish high-end welcome mat Melts 2 Inch of snow per hour; designed to be left outside for the entire winter season; Power Unit Included