1. BK, BF, EK, EF, FK, FF 2. Used with C7 ball screw 3. Good ... 5FF 2525241410639880799148.5FF 3030271897511795931117.511Ball screw end support bearingsFK AND FF TYPEORIGINAL: NINGBO CHINAHigh precision bearings BK10BK12BK15BK17 BK20BK25BK30BK35BK40BF10BF12BF15BF17 BF20BF25BF30BF35BF40EK6EK8EK10EK12 EK15EK20SEK20EK25 ... )20FK(WBK)25FK(WBK)30 FF(WBF)6FF(WBF)10FF(WBF)12FF(WBF)15 FF(WBF)20FF(WBF)25FF(WBF) ...