These came from a mid-1980's Bridgewood shaper, used on the hold down assemblies. They were never used, just hung around for the last 40 years. The thread is 8mm x 1.25 pitch, the threads are approximately 5/8" long. The metal rectangles are 13/16" x 1-3/16" x 3/16". The handles are approximately 2-11/16" long.