U-joints are for drag cars less than 2800 lbs. The 6198 is an economical pin-and-block design. It accepts 3/4" OD tubing into one side which is what we supply with our steering column kits. The u-joint can be bolted to the tube. The other side of this u-joint is 9/16 -26 spline. It is used to match the input shaft on the Pinto or Mustang II rack and pinion.