Camco PowerGrip RV 30-AMP Plug Type 125V Circuit Analyzer Adapter with integrated surge protection and fault indicationhelps protect your RV from power surges. 30-AMP male (NEMA TT-30P/30-AMP female (NEMA TT-30R), integrated surge protection up to 1,050 joules, diagnostic LED's provide indication of faults when you connect your electrical cord to the powerpedestal, indicates wiring issues when faults for reverse polarity, open neutral and other wiring issues, does not protect against sustained high or low voltages.