... lifting chain, and the material of the general for 20 M2, intermediate frequency quenching heat treatment, low wear, ... of the chain; High strength hook, material is commonly alloy steel, gesture type crane design to ensure that the slow ... , LTD was built in 1986 , has more than 20 years history , has accumulated rich experience in the sling ... praise of users. HSZ-KII Hoisting Manual Chain Block