... 8,10.9,12.9Surface:black zinc,parkerising,chrom plated and oxide coatingCertificate:ISO9001:2000The products have good ... C10458.Alloy steel: SCM435,10B21Surface FinishZn- Plated,Ni-plated,Passivated,Tin-plated,Sandblast and Anodize,Chromate,Polish,Electro Painting ... ,Black Anodize,Plain,Chrome plated Normal DiaM4-M30Heat TreatmentTempering,Hardening,Spheroidizing,Stress ...