... Alloy steel: SCM435,10B21Specification& gaugeM0.8-M10Surface FinishingZn- Plated,Ni-plated,Passivated,Tin-plated,Sandblast and Anodize,Chromate, Polish,Electro Painting,Black Anodize ... ,Plain,Chrome plated,Hot Deep Galvanize(H. D. G. ) etc.Heat TreatmentTempering ... and Evaluation7,Why Choose us? Cap head slotted screws with yellow zinc plated