Alpen hss super hexagonal drill bit - Diameter: 3.0mm. -Precision grinding, minimum tolerances, maximum concentricity precision. -Precise milling due to its optimized sharpening of the tip. -Made of top quality steel. -Resistant to breakage, due to controlled heat treatment. -Suitable for construction steels, easy-cutting steels, unalloyed steels, copper, brass, aluminum and plastic. -Hexagon stem.