1.Disc brake motor, fast braking, stable performance, long service life. 2. Thickened refined steel housing can effectively protect the internal components from impact. 3. High strength wear-resisting manganese steel hook, with good toughness and strength, not easy to break, hook head new design, weight is not easy to fall off. 4.Grade 80 national standard manganese steel chain, strong strength, strong tension, not easy to deformation.