... rock with the least possible loss of energyAccording to different drilling application, we have different design to meet customers with good ... , R25, R28, R32, R35, R38, T38, T45, T51, ST58, T60Button bit face design: Flat face, drop centre, Normal and Retrac body ... ): Spherical, ballistic and Conical. (Threaded R32, R38, T38, T45, T51, bit diameter: 45mm-127mm); (2) Main button bits diameters:R32-45mm ...