... Rods)Shank H22x108mm, H19x108mm, standard hex, Bit diameters include 20-42mm.2. Tapered drilling tools (Tapered Drill Steel)Including:Drill rods ... .button bits, cross type bits and chisel bits with(6,7,11,12 degree taper).Bit diameter:28mm-57mm.3. Extension drilling toolsButton bit, face ... 4. Down the hole hammers and DTH button bits (Down The Hole Drilling)Offer ir hammers,DHD3.5,DHD340a,DHD360,DHD380, ...