American mechanical suspension: 1, 88# for 13T axles 2,86# for 16T ... to machine to keep the concentricity. After process, to limit concentric degree within 0.02MM strictly.4. HJ brake ... heat resistant and not easy to distort.8. HJ type bolt is made of alloy material, which has the ... axle for customers choose to provide double safety.American type mechanical suspension:1, 88# for 13T axles 2,86# for ...