1.coal mining tools 2.ore mining, many type 3.good price,high quality 4.professional manufacurer 5.export many countries About products1. Integral drill steels (Integral Drill Rods)Shank H22x108mm, H19x108mm, standard hex. Bit diameters include 20-42mm.2. Tapered drilling tools (Tapered Drill Steel)Including:Shank H22x 108mm, (6, 7, 11, 12 degree taper) taper rods in most lengths.A comprehensive ...