... Rohs certification 4.material: stainless steel,carbon steel grade 12.9 mild steel hexagonal socket head cap screw 1)Standard ... so on.4)Surface of screw: plain, zinc Cr+3,Yellow Zinc Cr+6 5)Packing: bulk, box packing Material1.Stainless ... 35#,stainless steel, brass Grade: 8.8,10.9,12.9,SAE J429 GR.5/GR.8 4.Surface ... of screw: Black, Zinc Cr+3, Yellow Zinc Cr+6,H.D.G., Dacromet, etc. 5. ...