Detailed Product Description Professional Drill Bits1. We could produce according to customer's requirements based on standards: DIN8039, ANSI B212.15-1994, GB/T6335.1-1996, ISO5468 etc;2. Using special high quality carbide tip, and 40Cr or better material for body; 3. Heat-treatment: auto net belt stove handling equipment, could meet strictly torsion test;4. Flute type L, U, W etc produced by ...