"Ball screw is made of screw, nut and ball. it's function is to turn the rotary motion into liner motion, which is a further extension and development of ball screw. the significance of this development is to move into a rolling bearing from slidingaction. with little friction, ball screws are widely used in various industrial equipment and precision instruments. Applications: 1. Engraving machines; 2. High speed CNC machinery; 3.Semi-Conductor equipment; 4. Auto-machinery. http://www.sinier.cc/"