CNC machine ballscrew support unit 1.kinds of types:EF,EK,BK, ... ,FK,FF... 2.good quality,competitive price 3.rich stock CNC machine ballscrew support unitKinds of types:EF,EK,BK,BF,FK ... stock .They are high quality with reasonable price. This BK type ball screw support bearings are manufactured with poly amide so ...