... shock absorber piston rod, gas spring piston rod, cylinder piston rod, stampings, bushings, screws, spare parts and other auto parts. Features: 1 ... hardness:800HV-1000HV 9) Surface treatment: high frequency quench, quenching and tempering.10)We can produce the punch parts in different ... to client sample or drawing.Usage : hydraulic machine, pneumatic machines and auto machine, sport equipment.