Manufactured from High Speed Steel, Union Butterfield 4603 countersinks have a choice of 60, 82 and 90 degree angles for chamfering holes to take standard fasteners with 60, 82 and 90 degree heads. The High Speed Steel used in manufacture means they can be used for chamfering holes in a range of materials including steel, stainless steel and aluminum. With a single flute, designed to reduce vibration and chatter, providing a smooth chamfer operation, the reduced plain shank means larger diameter countersinks can be held in standard holders and chucks. 4603 single flute countersinks have a bright finish to prevent workpiece material from sticking to the cutting edges of the tool, ensuring clean and accurate surfaces.