About This Item Premium Quality: Made of high-speed steel with titanium coating, fully polished, forged and heat-treated, strong and durable. Titanium coating to reduce friction and heat from steel. Comes with a five-step drill bit, a 9-step drill bit from 4-20mm and a ten-step drill bit from 3-12mm. Hex Shank: Comes with a standard 6.35 hex shank mm, fits all power tools such as electric drills and electric screwdrivers. Hex shank can just stick drill bits stably in bit holder without screwdriver, prevent slipping when chuck. Dual flute design: Double flute design for optimal speed and precision, smoother cut, each step is clearly labeled with step depth diameter. Comes with little pressure and very easy to cut through wood, brass, steel, plasterboard and other surfaces. Exquisite workmanship --- Mark hole locations and starts drill bits and screws, preventing strays, heat-treated alloy steel punch with sharpened precision tip and corrosion-resistant brass body with non-slip knurled grip. Includes a handy nylon storage pouch to protect them. Multi-use: suitable for cutting holes in a variety of materials including mild steel, brass, wood, plastic, aluminum, copper, drywall, metal, fiberglass, PVC, etc. Easy to carry with nylon pouch, convenient to store in bag, car or home. Ideal for professional or home use.