... :3.5mm-6.3mm 4.Finish:zinc plated Hexagon washer head self drilling screw with tapping screws thread Standard:DIN 7504 ... , ANSI/ASME B18.64, Hex washers self drilling screw,Washer Head Self-Drilling Screw ,Pan Framing,drywall screw of self drilling ... screw), Hex Head self drilling screwSpecial and Non-standard products, against to the ...