... specially from blast furnace —MAXDRILL Tap hole Drill Bit (1)Diameter:38mm-70mm.(2) shape, carbide ... 3-blade type , steel cross bit , carbide cross bit ,button bit andetc(3)Package: in wood case or ... hole drill bits, according to customers' request, various tap hole drill rods and tap hole drill ... ; carbide 3-blade type, steel cross bit, carbide cross bit, button bit and etc. (3)Package: in wood ...