Product Bolt Material Carbon steel, Alloy steel, Stainless steel, Plastic and Copper. Size 1/2"-4", M3-M64 or non-standard as request & design Grade 4.8, 5.8, 8.8, 10.9, 12.9, 2, 5, 8, A307, A325. Surface Plain,Black,Zinc Plated(ZP),Yellow Zinc Plated (YZP)and Hot DIP Galvanizing(H.D.G.),Dacromet,Nickel Plated,Brass Plated. Sample Free sample can be sent for test Features Chemical resistance Dimensionally accurate Corrosion resistance Wear and tear resistant Remark OEM/ODM is available according to customer's drawing and samples