... /2",7 1/2",8 1/2",9 1/2",9 5/8",9 7/8",12 1/4",17 1/2", ... and seizure resistance of the bearing are improved. 2.Premium O-ring, Optimal seal compression and ... ",6",6 1/2",7 1/2",7 7/8",8 1/2",9 1/2",9 5/8 ... 9 7/8",12 1/4",14 3/4",17 1/2", etc. IADC Code:4-- Series, 5-- Series ... to minimum.Main Type AvailableSize: 8 1/2",9 1/2",9 5/8",9 7/8",10 ... 7/8",12 1/4",15",15 1/2",17 1/2", etc. IADC Code:5-- Series,6-- ...