This Collins 16 Pin 90 Degree Cannon Connector, is for the Collins TCS Radio System Transmitter. It is Part # SK-C16-90This Plug can also be modified to work with the RCA ARB Radio Direction Finder Set built in the 1940s. A new notch has to be cut in the body of the connector so the plug will line up properly. The connector is thick so you can use a jewelers file or dremmel tool to cut a new notch about halfway through the material.This Connector is New old stock and may have some discoloring. Some had a coating which made the finish uneven and they look a bit spotted. They have not had any of the connections soldered on and they have not been used.I also have the Connector for the receiver and the connector for the Control of the Collins TCS Radio System, in another listing.You Can also purchase the complete 3 Connector set at a discount!