... , standard hex. Bit diameters include 20-42mm.2. Tapered drilling tools (Tapered Drill Steel)Including:Shank H22x 108mm, (6, 7, 11, 12 ... rod.6. All kinds of casing bits for shield machine and construction tools.7. Round road planning bit for road milling machine ... , 25mm, 30mm, 33mm, 38mm, etc.8. Blast furnace tap hole drill tools. (Rod, Cross bits, button bits and X-type bits etc).