... diameters include 20-42mm.2. Tapered drilling tools (Tapered Drill Steel)Including:Drill rods with Shank H22x108mm,(6,7,11,12 degree ... pressure hammers CIR65a, CIR90, CIR110, CIR150,CIR170etc,DTH drill bits:60mm-254mm bits with flat face, concave design fit for the atlas ... 25mm,30mm,33mm,38mm,etc.8. Blast furnace tap hole drill tools.(Rod, Cross type bits, button bits and X type bits etc) Drill bits