The Camco 50M/50F 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 125/250V Dogbone includes surge protection up to 4200 joules. It is weatherproof, with durable power grip handles for safe and easy plugging and unplugging. NEMA 14-50 Plug and Receptacle.