Drill Bit, TCI Tricone Bit, PDC Bit manufacturer / supplier in China, offering Singe Roller Cone Bit 8 1/2′′ IADC537/637/737 Segment/Palm/Cutter of Tricone Bit, 110mm 4 Wings Diamond PDC Bit Drill Tools, Hot Sale Cn 12 1/4′′ PDC Bit for Hard Formation and so on.