... screwbolt screw, bolts and nuts, self drilling screw, self tapping screw, machine screw, furniture screwdrywall screw, screw nut, screw cap,High strength boltsSpecification ... various plating 2) Head style: pan, round, flat, oval, truss, hexagon flange, bugle, wafer, hinge, binding, button, truss3) Surface treatment: ... manufacture as your drawings or samples with Quality Gaurantee self tapping screw