Package Content: This step drill includes a 5-step drill and 1 automatic center punch. You can process 50 different types of diameter holes with this 5-piece drill bit. Titanium Coating: These step drill bits are made of high-speed steel with titanium coating, ensures durability and sharpness in standby, can reduce friction, cools cooler.. Automatic Center Stamp: The center punch can help you mark the center point of the hole you want to drill and make your process easier. Additional Usage: Our step drill bits are designed to easily cut/drill through steel sheet, aluminum sheet, wood board, plastic board, etc. (not including steel or any other harder metal). Suitable for home DIY and general construction and engineering Aluminum Storage Case: Our all drills are all in an aluminum box for your convenience and storage. And the aluminum shell protects the drill bit not easy to dull and prolongs the life of the drill. Automatic Center Punch The center punch can help you mark the center