1.Ball Screw Support Unit 2.BK,BF,EK,EF,FK,FF series 3.with Angular contact bearing ,good quality . 4.All types have stock ... . BK,BF Ball screw support unit :BK10,BF10; BK12,BF12; BK15 ... ; EK10,EF10; EK12,EF12; EK15,EF15; EK20,EF20.FK,FF Ball screw support unit :FK10,FF10; FK12,FF12; FK15,FF15; FK20,FF20; FK25 ...