Tricone Bit, PDC Bit, Hole Opener manufacturer / supplier in China, offering 17 1/2'' TCI Three Roller Cone Bit Chisel Drill Bit Factory Price, 6 3/4'' IADC 537 Rotary Drill Bit, Drilling Bits, Rock Drilling Bits, 7 7/8 ''200mm IADC 437 Sealed Bearing Tricone Bit Price and so on.