Yes. Those brackets were used on the rear valance of a 70 Challenger, and 70 Cuda with exhaust cut outs, but are commonly missing on many restorations I've seen. Here are pics from the FSM of the brackets on the Cuda and Challenger. There was apparently suppose to be a total of 4 per car, 1 on each side of the openings for the bumper guards. From what I've seen and documented, the AAR and T/A never used these reinforcements, as the rear body panel bumper mounting cross member does not have the holes for mounting them.