This is a 12 piece kit of new 11 gage repair plates to fix rusted and weak body mount locations on 1964 through 1972 GM Cars. It is 4 inches by 4 inches with a correct body mount 1 - 1/2 inch hole in the center. Cut a repair area out of your frame and trim the new plate to match. Put the repair plate into the open area and weld shut to provide a solid repaired mount area with the correct 1 - 1/2 mount hole. After grinding the weld smooth, the frame looks good. Most frames at the age they are now need several body mount locations repaired.