1.High strength steel frame 2.The friction disc and ratchet as replacement parts,more convenient. 3.It on ratchet part.The performance of maintenance-free bearing is close to rolling bearing,better corrosion resistance. 4.The material is alloy steel,passed heat treatment.It includes stamping safety latch.The hook frame is forging with more reliable quality. 5.The material of handle sleeve is oil resistant rubber. 6.Grade 80 load chain. 7.The stamping enlarged end ring supports 2.5times of rated load. 8.Brake seat and driving shaft connected by screw thread.