... Head Machine Screw with Zinc Plating and Length Ranging from 13 to 300mm Head type: CSK/flat head, truss head, trumpet head, wafer head, pan framing head, pan wafer head, hexagon head, pan ... 13 to 300mmHead recess: Philips 4 Ribbs, Pozi, Philips, Square, H.W.F undercut, ... H.W.H, serration, flower head and othersPlating: plain, yellow zinc, zinc, ... inspection Truss/Button Head Machine Screw