They came off my 74 Challenger. They were bolted to the underside of the rear frame rails I assumed at first they were for exhaust hangers but my stock single exhaust wasn't even attached to the right side. In retrospect I'm not sure why they would have installed one on each side on a single exhaust car. I was going to use them on the duals I am fabricating but I just couldn't get them to work without additional custom made bracketry. Since that was the case (for my resources) I went ahead and made brackets that served the purpose in place of these and used the stock holes.