This is the only heated doormat available that provides heat up to 50 F higher than the ambient temperature, allowing you to keep your entryway free of ice and snow, unlike typical salt applications that harm grass or plants nearby when snow melts into slush, require constant re-application, and stain surfaces when tracked indoors. Also useful for keeping your feet warm during winter cookouts, the durable mat has a ribbed surface that provides additional traction. Melts 2″ of snow per hour.