... , Normal and retrac body.tungsten carbide(Buttons):Spherical, ballistic and Conical.(Threaded R32, T38, T45,T51, bit diameter: 45mm-127mm ... );Couplings sleeves-manufactured with a middle stop to prevent walking along the thread. Include ... R32,R38,T38,T45,T51)Shank adapters-carburized and manufactured with tight tolerances and controlled straightness.4. Down the hole ...