The Reese 6562 Trailer Emulator (7-way RV blade) lets you test a tow vehicle’s trailer-lighting, 12V charge, and brake controller outputs without hooking up a real trailer. Plug it into the vehicle’s 7-way and quickly verify circuits for left/right turn, tail/running, reverse, electric brakes, and 12V auxiliary. Ideal for troubleshooting wiring issues, confirming installs, and shop check-outs after service.