... ''x1/8'' etc2Bearing Bar Pitch12.5, 15, 20, 23.85, 25, 30, 30.16, 30.3, 32.5, 34.3, 35 ... , 38.1, 40, 41.25, 60, 80mm etcUS standard: 19-w-4, 15-w-4 ... , 15-w-2 etc. 3Twisted Cross Bar Pitch38.1, 40,50, 60, 76, 80, 100, 101.6, 120mm, 2'' & 4'' etc ...