The Century Drill and Tool 5/16 in. x 3-3/4 in. L Cobalt Steel Stubby Drill Bit (Straight Shank, 1 pc) is a high-performance bit designed for drilling tough materials like stainless steel, cast iron, and other hard metals. Its stubby length provides better rigidity and reduces walking, while the cobalt steel construction ensures long life and heat resistance under heavy use. This straight-shank design fits standard chucks and delivers reliable, accurate drilling in tight or confined spaces.