1.Sizes range from 3 7/8" to 26" . 2.Reliable bearing and lubrication system 3.MOQ: one piece 4.The best price ... mining applications.5. 5.Current Main AvailabilityDiameter/InchIADC CODE3 1/2 211, 121, 241, 537….3 7/8 131, 211, 537 ... , 537….4 3/4 131, 211, 537, 517….5 1/2 131, 211, 537, 517….6 211, 121, 241, 537…. 12 ... 1/2 211, 121, 241, 537….14 3/4 131, 211, 537 ...