Extremely robust and aggressive full carbide bit head, 4 cutting eges for extraordinary service life and tool life in strong concrete, The wear marking on both sides of the main plate serves as indicator to evaluate the dimensional conformance of the dowel holes., The 4-spiral helical geometry ensures low-vibration drilling behaviour and low spiral wear, 90° centering point for precise spot drilling and little breakage at the edge of the drilled hole, Ideal for use in reinforced concrete and hard natural stone