UL & cUL approved and Listed, Heavy-duty for Welder, 100% copper conductor inside. Female with lighted, easy to find if working or not. Welder 3-prongs NEMA 6-50 Connector, for 50 Amp / 250 Voltage. STW 6AWG/3C stranded wire extension cord, support max 50 AMP loading, Max Rate 12500 Watt (250V). Molded with electroplate copper terminal in order to avoid surface oxidation effectively. Universal to All Other Brands 6-50 Welding Machine 3-pole. Six choices of length. (15 Feet, 20 Feet, 25 feet, 50 feet, 75 feet, 100 feet)