The Motobilt Jeep spring over offset perch was designed to work with an axle tube diameter of 2.5 inch on the front of the Jeep YJ 1987-1996.
The laser cut steel perch is built to work with 2.5 inch wide springs and has 3 center pin holes for adjusting wheelbase for steering clearance. The perch is offset on one side so that when mounted it can mount up close to the differential housing. This allows you to perform a spring over on your Jeep YJ factory front axle. If you attempted to use a standard perch your springs would end up uneven and put your suspension in a bind. These perches are made out of 1/4 inch thick steel plate that is laser cut, CNC bent, and then welded for the ultimate in strength.