1 PC Single Universal Joint Stainless Steel 3/4" DD X 3/4" DD Universal Steering Shaft U Joint Coupler. Function:This U-Joint is used to connect a 3/4"DD steering shaft to another piece of 3/4"DD. How to Install:Open the hood to check the front of the steering wheel;Find steering shaft on drive line system;Unlock the old steering shaft and remove it; Put the new u-joint steering shaft;Tighten the set screws and jam nuts.