Tin plated copper stab to create a reliable permanent and corrosion resistant connection. Ensures its ground circuitry is functioning properly by automatically running diagnostic testing on a periodic basis. Should a problem be detected the circuit breaker will trip and will need to be replaced. Unit provides protection against overloads short circuits and ground faults. Class A 5mA ground fault circuit interrupter. Wire range is #14-8 AWG CU/#12-8 AWG AL. UL Listed. 4.5" height x 1.25" width x 3" depth .479 lb.