7 1/2 Inch 190.5mm IADC437/537/ 637 Tricone Rock Drilling Roller Cone Bit
China 7 1/2 Inch 190.5mm IADC437/537/637 Tricone Rock Drilling Roller Cone Bit, Find details about China Tungsten Carbide Insert Bit, Hard Formation TCI Tricone Bit from 7 1/2 Inch 190.5mm IADC437/537/637 Tricone Rock Drilling Roller Cone Bit