18-Ft. Electric Water Pipe Freeze Protection Cable18' automatic pipe heating cable. Pre assembled and ready to install, the cable prevents pipes from freezing, keeping water flowing to 40 degrees, using an energy saving thermost. Will accommodate pipe diameters up to 1 1 2 inches. Simply run the cable straight along the pipe and valves according to the included instructions, affix with premium application tape and insulation, then plug into a ground fault protected electrical outlet.