Special lengths, right-hand cutting, with cylindrical shank, precision-ground twist drills in industrial quality for drilling alloyed and unalloyed steels, gray cast iron, malleable cast iron, copper alloys, nickel silver, graphite, sintered iron, wide flutes and reinforced core are the main features, this enables a drilling depth almost corresponding to the twist length , and good chip removal, point angle 118°, surface blued from 1.0 mm, all dimensions from 4.0 mm with special "AC" grinding, industrial quality suitable for NC machines, precise thanks to modern grinding processes, break-resistant thanks to CNC-controlled heat treatment