The Camco 30M/30F AMP Circuit Analyzer helps protect your electrical equipment from improperly wired electrical boxes by visually indicating faults before you connect your RV’s Power Cord to the electrical box. The 125V Dogbone includes surge protection up to 2100 joules. It is weatherproof, with durable power grip handles for safe and easy plugging and unplugging. NEMA TT-30 Plug and Receptacle.