... following types: A. Taper button bitTapered button bit(28mm, 30mm, 32mm, 33mm, 34mm, 36mm, 38mm, 40mm, 42mm, 44mm and so on. With ... 19mm, 22mm, 25mm; Shank hex, 19mm, 22mm) Internal Drill rods(chisel bit integral rod. 19mm, 22mm; Shank hex. 19mm, 22mm) B. Thread ... , 89mm, 102mm, 115mm, 127mm and so on. R25--38mm, R25--41mm, R28--38mm, R28--41mmR32; R32--45mm, R32--76mm, R32--89mm, R32 ...