Bolt and screw type heads produced by our company include hexagonal, foursquare, hexagonal cross grooved, hexagonal sphere, hexagonal convex, convex sphere, external quincunx convex, internal hexagonal, internal hexagonal convex, cross grooved panhead, cross grooved big flathead, quincunx grooved panhead, internal hexagonal big flathead, cross grooved countersink, internal hexagonal countersink and cross grooved semi-countersink etc as well as motorcycle's front wheel axle, rear wheel axle, flat fork axle, engine's hung bolt, cylinder bolt etc high-strength axle type fastening units.