Detailed Product Description 1) Standard: ISO, DIN, BS, NFE, ASTM and ANSI 2) Material: spring steel, stainless steel 18-8 SS / A2 304 SS / A4 316 SS 3) Class: high strength (heat treatment, hardened) 4) Finish (surface treatment): plain, black, oxide, zinc plated (white / blue / yellow), hot dip galvanized, nickel plated 5) Packing: Bulk or small packing according to buyers' instructions