... rock with the least possible loss of energyAccording to different drilling application, we have different design to meet customers with ... , R35, R38, T38, T45, T51, ST58, T60Button bit face design: Flat face, drop centre, Normal and Retrac body.Tungsten carbide (Buttons ... we become one of the most credible Chinese manufacturers in drilling industry. MAXDRILL ROCK TOOLS satisfy our clients with SAVING ...