The "boss" is a "boss thimble screw" used to position and fix the mold. It is installed and fixed on the injection mold, usually on the moving mold side of the mold. The main function of the "ejector pin screw" is to fix the "ejector pin" on the mold so that it will not move or loosen during injection molding. At the same time, the "boss thimble screw" can also control the position of the "boss" by adjusting its length, thus adjusting the closing height of the mold and the opening and closing stroke of the mold.

"Spindle thimble screw" usually adopts hexagon or external hexagon, which is convenient for fastening and adjustment with wrench or screwdriver. Its length and diameter are selected according to the size of the die and the torque it needs to bear.