... /ASME,ISO,GB 4.surface treatment :zi 1.Materials: stainless steel, carbon steel, alloy steel, copper, etc2.Surface treatment: plain, blue zinc, color zinc ... .Length:4MM-50MM screw6 Self-clinching screw7.Stainless steel screw8.Various kinds of self-clinching screw available9.Packing: general export packing poly bag ...