MULTI-SIZE: 1pc 15-step drill bit (4-32mm), 1pc 9-step drill bit (4-20mm), 1pc 13-step drill bit (4-12mm). Three sizes are available to meet your needs. QUALITY MATERIALS: Classic high-speed steel, titanium coating on the surface, proven performance and durability in drilling holes in plastics, wood, aluminum, copper, stainless steel and many other types of sheet metal. Titanium alloy drill bits are especially suitable for processing copper and aluminum parts / die steel / spring steel / cast iron parts / iron and other metal materials. PRECISE POSITIONING DRILL BIT: When you press the surface, it produces automatic, high-impact, spring-loaded striking force, and an adjustable hood can adjust the striking force. LASER ENGRAVING: The size is laser engraved into the metal, so it will not wear out even if it is reused, making it easy to drill accurately. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store