... system 20 years history Milled Tooth Rock Roller Bits: 7 7/8 to 14 1/2 ModelTCI BIT, STEEL ... unionDelivery termsBy sea or by airDelivery timeWithin 3 to 7 daysMarketCanada, USA,Middle east ,Africa,Europe Hejian Huanyu ... rotary bit, TCI tricone bit,PDC drill bit ,diamond core bit,bicenter bit,single cone bit , reamer bit, ... ~174.63 3/4-6 7/8294-53980-60187.3~241.37 3/8-9 1/2539-83360-40hardSandy, Shale ...