Reese 74607 is a 7-Way Blade to 4-Way Flat Wiring Adapter that allows electrical connections between a 7-way blade receptacle and a 4-way flat trailer plug. It features an LED circuit tester to confirm that each connection is operating properly, ensuring a secure and reliable connection between your tow vehicle and trailer. With its simple plug-and-play design, the Reese 74607 makes it easy to establish electrical connectivity for various lighting functions, including tail lights, turn signals, and brake lights.