.Premium Sub-Micrograin Solid Carbide Jobber Length DrillALTiN Coated2 Flute25° Helix118° Split Point Jobber Length These drill bits require rigid toolholding and workholding to be run properly and avoid breakageMetric SizesALTIN Coating: A high performance coating for drilling stainlesssteels, carbon steels, alloy steels, and cast iron.