[Don Rogers]

Steve, Original B-2454 pads had a conventional 7/16-20 thread and required a nut and lock washer to hold them in place. 40-2454 pads changed the threads to a 1/4" pipe thread. This eliminated the need for a lock washer and nut. I'm guessing that thru ignorance or cost cutting, the repop houses made both pad threads with standard threads.