... 3)quality be assured 4)competitive price and service 1)Equipment:stamping machines,Hydraulic press machines,Auto-Turning ... and argon-arc welding 2)Material: iron, carbon steel, stainless steel, brass, copper, alloy steel, aluminum, cold rolled steel3)Surface treatment: kinds of ... Powder, Anodizing, E-coating, Silkscreen, Heat treatment, Black oxid metal non-stard stainless steel tension coil spring