RCA male to RCA male cable. Use to connect an RCA PTT on a radio to the RCA PTT input on HHI Radio Pro. It can be used in other places those connectors are used too, but this is the main use case Halibut Electronics is selling it for.
You can get similarly suitable cables elsewhere, or might even have some on-hand already. We offer them for sale here as a convenience, and we make sure the cables we sell are good quality and meet all the requirements.