... , 34, 38, 40, 43, 50mm Connect: hex19, hx22, hex25 taper rod Tips: spherical, parabolic button Specialisted in producing of varies type ... , 25mm; Shank hex, 19mm, 22mm) Internal Drill rods(chisel bit integral rod. 19mm, 22mm; Shank hex. 19mm, 22mm) B. Thread Button BitThread ...