About This Item Premium Quality: Made of titanium coated high speed steel, fully polished, forged and heat treated, strong and durable. Titanium coating to reduce friction and heat from steel. Comes with 4-12mm 5-step drill bit, 4-20mm 9-step drill bit and 4-32mm 15-step drill bit. Hex Shank - Comes with Hex Shank 1 or 4" standard, fits all power tools like electric drill and electric screwdriver. Hex shank can just stick the bits stably in the chuck without screwdriver, avoid slipping when tightening. Dual flute design: Double flute design for optimal speed and precision, smoother cutting, each step is clearly labeled with the diameter of the depth in steps It comes with a little pressure and very cutting easily through wood, brass, steel, sheet metal and other surfaces. Exquisite workmanship: Mark hole locations and start drilling holes with drill bits and screws, preventing the slip - Heat treated alloy steel punch with precision sharp point - Corrosion resistant brass body with non-slip knurled grip. Includes a handy nylon storage bag to protect them. Versatile: suitable for drilling holes in a variety of materials, including mild steel, brass, wood, plastic, aluminum, copper, sheet metal, metallic materials, fiberglass, PVC, etc. Easy to carry with nylon bag, convenient to store in handbag, car or home. Perfect for professional and home use.