... as well, and our dominant products are chisel bits, cross bits, buttons bits, DTH bits with high, medium and low air pressure, symmetric ... foundation constructions etc.Our company produces advanced drilling tools with the top-grade manufacturing equipments. The mission is ... Drill Bits---Diameter: 51mm to 127mmThread Type---R22,R25,R28,R32,R38,T38,T45,T51Face Shape---Plate, Concave, Convex.Bit Shank ...