... Degree 3.Water Hole: 2 4.Body: Normal Rock Bits The Advantages Of Taper Drill Rock Bits1. Higher Quality2. With ... Reasonable price4. Better After-Sales ServiceThe Taper Drill Rock Bits are made from grade hard alloy and special steel, generally ... of 50mm. The drill tools are used in metallurgy mine, geological exploration, water conservancy construction, electricity, traffic, tunnel, quarry, national ...