... made by advanced CNC lathe, pass ISO, ANSI,DIN quality certification. high precision and good wear resistance. 2, surface treatment is ... MaterialC45, A3, 40Cr, 20CrMnTi, 42CrMo, copper, stainless steel and so on as per your requestprocessForged or castingHeat treatmentHigh frequency quenching, heat ... negotiablePackagingInner plastic bag and outer carton box or customer requirement. weld on sprocket