Universal Coupling Set transmits smooth power between angled drive shafts in boats, trains, autos and other model mechanisms. Robust nylon ball-and-socket joints and 3/32 inch square brass drive rod transmit power at shaft angles up to 45 degrees. Sliding-ball technology compensates for the normal change in distance between the ends of the shafts as they change position. Set includes enough components to assemble 4 complete heavy-duty universal couplings up to 3-1/8 inches long. Overall diameter is 9/32 inch. Sockets press fit on 3/32 inch diameter shafts, but other shaft sizes can be used by bushing or boring out the socket.