Block up

The utility model relates to a block up, including the block up body, its characterized in that: the block up body includes head and screw thread portion, the outer wall of screw thread portion is provided with the external screw thread, the centre of head has been seted up circular revolving and has been twisted the chamber to screw thread portion direction is sunken, should circular inner wall that revolves wrong chamber be the hexagon structure, the diameter of the outer wall in circular soon wrong chamber is 0.53 with the ratio of the diameter of head the utility model discloses lie in: the circular diameter of the outer wall who revolve to twist the chamber be 0.53 with the ratio of the diameter of head, has improved the bulk strength of head, and external hexagonal spanner inserts circular revolving and twists the chamber and revolve and twist the in -process, and this head receives external hexagonal spanner and revolves when wrong, and this head is difficult to appear the phenomenon of rupture emergen