I have noticed on some, but not all, model 5 (exposed winding wheels) 16s Hampdens, at the edge of the movement ,between the click and the barrel bridge screw, there is what looks like the polished end of a screw coming thru the plate from the inside.The movements in the lower 3 mil. serial#'s have them, the higher #'s don't.My 19j Railway, # 3170435 has it, and it is corroded.Does anyone know if that's a screw or a dowel pin?Seems to have been eliminated on higher numbered movements.Sorry, I can't post a picture. Thanks, Ted.