Conical-pilot countersink consist of a rubber spring, which prevents cutting until the pilot is seated and pressure is applied to the workpiece. The cutter extends after conical pilot has seated. Conical pilot under spring pressure eliminates vibration enabling the counter-bit to produce chatter-free concentric cuts. It is used on CNC machining centers, robotic arms, manual mills, turret lathes in lathes tailstocks and on drill presses. Its tungsten carbide blades are relieved with chip breakers.