Industrial Cobalt Steel Step Bits Set (5-Piece). Drill Bit Type: Step. Drill Bit Type(s) Included: Step. Features: No Additional Features. Number of Pieces: 5. Tools Product Type: Power Tool. Drill bits are designed to enlarge a hole as the bit drills through the sheet metal. Each step on the bit is larger in diameter than the step before. Smaller step drill bits are self-starting and no pilot bit is required to start the hole. The Stark cobalt steel bits provide longer life and cut faster than high speed steel. 2 spiral flutes, automatically deburrs as you drill and provides better chip removal. This 5-piece set with case is a great choice for professionals and do-it-yourselfers alike. The cobalt steel reduces friction and will run cooler with no need for a pilot hole. Features a 3-sided shank to prevent slip in the drill chuck and bits automatically deburrs holes as you drill. Comes with storage and organization case.