The Camco PowerGrip RV 30-Amp Circuit Analyzer Adapter with Integrated Surge Protection and Fault Indication helps protect your RV from power surges. Diagnostic LEDs indicate wiring faults when you connect your electrical cord to the power pedestal. The circuit analyzer indicates faults for reverse polarity, open neutral and other wiring issues. Includes integrated surge protection of up to 1,050 Joules. 30-Amp male (NEMA TT-30P)/30-Amp female (NEMA TT-30R). Does not protect against sustained high or low voltages. Patented.