A variety of railway fittings such as a tunneling limit bracket, the wrist arm base body is used for a wrist arm column, a hard beam and a suspension column, and the single, double or three wrist arm devices are mounted and fixed. Use Q235A material. Forged hot dip galvanizing process. Its main performance, 1. The maximum horizontal working load is 7.4kN, the maximum vertical working load is 4.9kN.2. The maximum horizontal breaking load is 22.2kN, and the maximum vertical breaking load is 14.7kN.