The suspension chain uses a lifting chain to require high distance standards for the chain. Because the cable is not only one -leg and a leg and a polypace. If the pitch error is large, the cord will be obvious in different lengths. The inner width of the chain of the cable is relatively large, so that after the chain and connecting parts are connected, the chain ring and connecting parts are flexible. The surface of the cable is often used for black. It can delay the rust of the chain and the appearance is more beautiful.