The seat binder bolt is on the backside of the seat clamp. The clamp is not integrated into the frame, it is a collar binder. This aspect of the frame leads me to believe it is probably a later 70's lower end frame. I tried to take some pics this morning but the batteries were dead in my digital camera. Will try again tonight. The wheels are at the LBS being trued and tensioned so the pics will just be of the frame.