... tapered button bit, retract button bit, thread button bit.With ISO certificate & quality control.Button bits with 6tips, 7tips, 8tips, we do them ... 42mm, 44mm and so on. With different degree taper) Tapered Rod (Rod 19mm, 22mm, 25mm; Shank hex, 19mm, 22mm) Internal Drill rods ... (chisel bit integral rod. 19mm, 22mm; Shank hex. 19mm, 22mm) B. Thread Button BitThread button bit (33mm, 35mm, 45mm, 51mm ...