... , face design :Flat face, drop centre, Normal and retrac body.tungsten carbide(Buttons):Spherical, ballistic and Conical.(Threaded R32, T38, T45,T51 ... ,U94,U95,U118 And coal bolting bit and coal bolting rod.6.All kinds of casing bits for shield machine and ... ,33mm,38mm,etc.8.Blast furnace tap hole drill tools.(Rod, Cross type bits, button bits and X type bits etc ...