Cable installs fast and easy. Each package contains grounded plug, built-in thermostat, and instructions. Cable has weather-resistant PVC outer jacket and inner insulation. Keeps water flowing down to -40 degrees Fahrenheit. Features power indicator light, 3-wire grounded cord, and plug. 7 watts per foot, 120 volts. Approved for rigid plastic and metal pipe. UL (Underwriter's Laboratories) listed.