... ISO9001. 4. OEM is available. Specification: Product nameScrew, Different function of Screws BrandWDMaterialCarbon Steel (35#, 45#), Alloy steel (35crmo, 40cr) ... BS, ANSI, JIS, DIN Surface treatmentBlack oxide, Zinc plated, hot galvanized, plated dacromet and bonderizing.ColorBlack, zinc, yellow, silveryRemark:1 ... or samples.2. Non-standard product is available. Screw, Different function of Screws