These were developed as part of our Coil Spring set options and we have found them to be too useful to be just made for that. This one is 4" X 4" square useable area if using the outside portion and 3.5" X 4" if using the inside area. They are 1/4" A50 plate made so they can rest on or under the frame and get a weld on 2 surfaces of the frame. They can be used inboard or outboard of the frame. Some of the uses we have thought of include Body Mounts, Roll Cage Tie in, Coil Spring mounting, Shock mounting, Motor mounts, & Crossmember Mounting. I am sure you will think of more. These are sold in pairs.