Flexible coupling used to join rotating shafts; For example, the drive shaft in a car. In a typical universal joint the ends of the shafts to be joined end in U-shaped yokes. They dovetail into each other and pivot flexibly about an X-shaped spider. This construction allows side-to-side and up-and-down movement, while still transmitting rotary motion. We provide quite a few kinds of them, especially for cars.