I borrow a utility trailer from time to time that has a relatively short connector for the lights.  The owner has a long lead on his towing vehicle, so it's not a problem for him, but my truck has the connectors on a bracket bolted to the bumper; the lead on his trailer barely reaches, and has pulled out on a hard right turn.  This extension is perfect, completely solves the problem for just a few dollars, with no modification needed to the wiring on my truck or his trailer.