Over the years we have seen failure of the rivets that hold the exhaust heat shield to the mounting bracket. The solution was to spot weld the stainless steel mounting bracket to the stainless steel heat shield thus eliminating the possibility of rivet failure. Adding additional spot welds insures reliability. They are offered in two sizes, 2 inch and 4 inch to cover most applications.
Per the supplier: Our 4" shield is 4" long (OD), 2 1/2" wide (OD) and the curve measures 3" (OD). I hope this is helpful.