ThunderBit Cobalt Sets Set 29 Piece Cobalt, HSS Bronze Oxide 1/16"-1/2" by 64ths

Features

• Thunderbit® drills have a special heavy-duty core that guarantees increased strength and reduced breakage. Unique spiral flute design improves chip ejection and coolant flow to the point. M42 Cobalt steel for use in harder, more abrasive materials.