HeatTrak. The Residential Heated Walkway Mat, suitable for use on outdoor surfaces such as turf and concrete, can be left outside throughout the winter. Each 300-watt mat melts snow at a rate of 2 inches per hour down to 0 F. The 20-by-60-inch mats feature watertight connector cables for covering larger areas in combinations of up to five walkway mats, 18 safety stair treads, or a combination thereof, on a single control unit. 973.357.9797. www.heattrak.com.