Ball Screw is a high-efficiency feed screw with the ball making a rolling motion between the screw axis and the nut. It in motion under an external load receives repeated stress on its raceways and balls. When the stress reaches the limit, the raceways break from fatigue and their surfaces flakes like scales. Compared with a conventional sliding screw, this product has drive torque of one-third or less, making it most suitable for saving drive motor power.