Vastar Titanium Step Drill Bit Set & Automatic Center Punch 28 SIZES INDIVIDUAL DRILL BITS IN 3: This set includes three standard step drill bits that replace 28 individual drill bits, comes with one 3/16" to 1/2"six-step bit, one 1/4" to 3/4" nine-step bit, and one 1/8" to 1/2" 13-step bit. STRONG DURABILITY : Made of strong M2 steel with titanium coating, the bits have strong durability. avoiding the inconvenience of a tri-flat shank to ensure a firm grip. EASY DRILLING: Two-fluted design provides faster, smoother cutting . Provided with small pressure and the sets can cut through wood, sheet metal, steel and other surfaces. AUTOMATIC CENTER PUNCH: Delivers an automatic, high-impact, spring-loaded strike when pressed against surface, adjustable cap regulates striking force WIDE USAGE: Marks hole locations and starts drill bits and screws, preventing wandering, heat treated alloy steel punch with sharp precision tip, corrosion-resistant brass body with non-slip knurled grip