Yost JOSTRO50E pin type (also known as "duckbill type" and "bell mouth type") traction hook adopts full pneumatic control design. The unique rocker (yost patented technology) tappet is used to trigger the closure, and the mechanical structure automatically triggers the locking of the traction bolt, so that the trailer can be connected and disconnected at any horizontal angle. In addition, the traction hook is fixed by the through bolt, which is very simple to assemble and disassemble, and the rotatable lock pin can reduce the wear caused by the long-term bump of the vehicle.