... Thread Drill Bits---Diameter: 51mm to 127mmThread Type---R22,R25,R28,R32,R38,T38,T45,T51Face Shape---Plate, Concave, Convex.Bit Shank ... & Coupling sleeve---R22,R25,R28,R32,R38,T38,T45,T51 Down-The-Hole Tools1) DTH BIT---65MM ... .5bar)Concave---Suitable for medium-hard rock (1033.5bar~2067bar)Plate ---Suitable for had rock ( more than 2067bar) Drill RodSteel Drill Rod ...