DTH Hammer, DTH Bit, Button Bit manufacturer / supplier in China, offering Factory Price 8 1/2 Inch Roller Cone Bit, 215mm IADC537 Tricone Drill Bit for Water Well Drilling, T38 T45 T51 Top Hammer Thread Button Retrac Drill Bit for Rock, 89mm Water Well Drill Pipe DTH Rod with 89mm Water Well Drill Pipe DTH Rod with API 2 3/8" Reg and so on.