Rock Drill Bits, Roller Cone Bits, Button Bit manufacturer / supplier in China, offering Manufacturer Supplies 7" Tricone Bit for Water/Oil Well Drilling, API Factory Price 15" IADC537 TCI Tricone Bit/Rock Bit/Drilling Bit, API 7 7/8 Inch 200mm TCI Tricone Bit/Roller Cone Bit/Rock Drill Bit and so on.