WHAT YOU GET: 1 x Aluminum Housing, 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 Bit. AUTOMATIC CENTER PUNCH: The 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 case can provide convenient storage and carrying. DUAL CUTTING BLADES AND THREE-SIDED ROD: Double cutting blades and X-type opening design ensure more cutting faster and smoother; 3-sided shank design can prevent the drill chuck from slipping; With the smallest pressure, the sets can cut through wood, sheet metal, steel and other surfaces. HSS AND TITANIUM COATING: High speed steel makes the step drill bit set more durable, titanium coating makes it easy to cut steel sheets, aluminum sheets, copper, plastic and wood and many other types of sheet metal. TIME SAVING: Cover Assorted step sizes allow different holes to be drilled or enlarged in a drill bit without constantly changing bits. The size is laser engraved into the metal, so it can be drilled precisely and will not wear out even if used for a long time.