Tricone Bit, PDC Bit, Hole Opener manufacturer / supplier in China, offering 8 1/2′′ 215mm IADC117 Big Teeth Steel Tooth Tricone Roller Bit, 7 1/2′′ IADC 217 Milled Tooth Tricone Drill Bit, 12 1/4′′ IADC 127 Tricone Roller Drill Bit Steel Tooth Water Well Drilling Bit Price and so on.