EATON WD112 50-Amp 125-Volts 2-Pole 3-Wire Surface Mount Range Power Receptacle, Black Features heavy galvanized steel and mounting strap to resist corrosion. Patented lay-in terminals accept up to #4 AWG Back features concentric knockouts and an adjustable cord clamp to allow wiring from back and bottom Features 3-Pole/3-Wiring with a Nema Standard of 10-50R with 125/250 Voltage To be used with aluminum or copper wiring