our dominant drill bits are chisel bits, cross bits, buttons bits, DTH bits We are a professional company which is ... products. Tapered Drill BitType --Chisel Bits / Cross Bits / Button Bits Diameter---28mm,30mm 32mm,34mm,36mm,40mm,42mm,44mm Thread Drill Bits---Diameter: ... 51mm to 127mmThread Type---R22,R25,R28,R32,R38,T38,T45,T51Face Shape---Plate, Concave, Convex.Bit Shank ...