... with high quality of best quality alloy steel bar and tungsten carbides, MAXDRILLThread button bits made with high quality of ... best quality alloy steel bar and tungsten carbides, through heat treatment so that it can withstand ... , T51, ST58, T60 Button bit face design: Flat face, drop centre, Normal and Retrac body. Tungsten carbide (Buttons): Spherical, ballistic and Conical. ( ...