... R28, R32, R35, R38, T38, T45, T51, ST58, T60 Button 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 ... credible Chinese manufacturers in drilling industry. MAXDRILL ROCK TOOLS satisfy our clients with SAVING YOUR PURCHASING COST and SAVING MORE USAGE ...