There's not a U joint.

The wing socket permits a motion similar to a universal joint, Fig.

He invented the universal joint, which can move in many angles.

The prime essential in a well working harmonograph is a properly constructed universal joint.

Question 1, the universal joint, had come up in the mock exam, so students were well-prepared.

The man-made universal joint has a wider range of movement, possesses greater strength, and is more perfect mechanically.