WHAT YOU GET: 1 x Aluminum Case, 1 x 5-13mm, 1 x 3-13mm, 1 x 6-19mm, 1 x 5-22mm, 6-35mm Step Drill Bits, 1 x Automatic center punch and 1 x Twist drill. AUTOMATIC CENTER PUNCH: Automatic center punch provides an automatic, high-impact, spring-loaded strike on the cap; Its brass body has a deep, knurled surface for non-slip control. The aluminum protective casecan provide convenient storage and transportation. DUAL CUTTING BLADES AND THREE-SIDED SHANK: Double cutting blades and X-type opening design ensure faster and smoother cutting; 3-sided shank design can prevent the drill chuck from slipping; With the mostsmall pressure, sets can cut through wood, sheet metal, steel and other surfaces. HSS AND TITANIUM COATED: High speed steel makes the step drill bit set more durable, titanium coating makes it easy to cut steel plate, aluminum plate, copper, plastic and wood and many other types of sheet metal. TIME SAVING: Covering assorted pitch sizes makes it possible to drill or enlarge different holes in one drill bit without constantly changing drill bits. The size is laser etched into the metal so it can be precision drilled and will not wear offeven if used for a long time.