hex flange head self drilling screw material:Stainless Steel 316, ... .Certificate: ISO 9001:2000 hex flange head self drilling screw 1.Machining method: cnc Turning, Milling, Drilling, threading, stampling, punching ... etc2.Surface finish: Polishing, and Chrome plating, zinc plating, blackening, Nickel plating, Electrophoresis, Anodization3.size:Various kinds of ...