MAXDRILL ROCK DRILLING TOOLS: --Integral drill rod (HEX.19MM, HEX ... connected bit(chisel bit, cross bit, button bit ) --Extension drilling tools : thread R22, R25, R28, R32, R38, T38 ... : R22, R25, R38, T38, T45, T51 -Self-drilling rock bolt (R25, R32L,R32N,R32S, R38N,R51L,R51N,T76N,T76S ... ) -Self-drilling rock bolt accessories: (coupling, nut, plate, steel bit, cross ...