... Type---R22,R25,R28,R32,R38,T38,T45,T51Face Shape---Plate, Concave, Convex.Bit Shank & Coupling sleeve---R22,R25,R28,R32 ... ---65MM to 254mm.2) DTH Hammer---76MM /90MM /110MM 3) Face ShapeConvex---Suitable for soft rock ( less than 1033.5bar)Concave ... ---Suitable for medium-hard rock (1033.5bar~2067bar)Plate ---Suitable for had rock ( more than 2067bar) Drill RodSteel Drill ...