Screw head with double cross groove (Machine-translation by Google Translate, not legally binding)

摘要

Head screw with double cross groove, characterized by having at its proximal end two rectilinear grooves, equal to each other in length, width and depth. These grooves are crossed at their midpoint in a plane transverse to the axis of the screw, standing perpendicular to one another. The crossing point will also coincide with the geometric center of the screw head. (Machine-translation by Google Translate, not legally binding)