Review on Reese Towpower 74184 Plastic 4-Pin Flat to 7-Pin Round Vehicle End Adapter - Enhanced SEO by Eddie Simpkins

We have this to attach our truck to our pop up camper. Everything came together pretty easily. There are three wires that do NOT need to be connected, these are options. However, it is very important that you ground it well. If you don't have good ground, the light won't work properly. For example, when we applied the brakes, the taillights went out completely and the brake lights didn't come on. We had to take a piece of sandpaper and clean a really clean part of the truck's underbody and then sand it down. Once we did, the system worked great as we cruised around the country with ease, even with our old folding camper.