All-Purpose Step Bit Kit With 4 Common Step Bits Sizes (1/2, 3/4, 7/8, and 1-3/8-Inch) Cuts holes In Wide Variety of DIY Applications And Materials (Up To 16 Gauge Steel, Plastic, Aluminum, Wood), 2 Spiral Flutes On Each Step Drill Bit Remove Chips And Help Pull The Bit Through Material For Faster Cutting, Titanium Nitride Coating Dissipates Heat For Longer Bit Life, 1/4-Inch Hex Shank For Firm, Positive Grip In Impact Driver And Standard Drill, Split Point Tip Quickly Starts Hole Cuts And Prevents Drifting When Pressure Is Added, Kit Comes With A Convenient 1-Ounce Oil Bottle For Lubrication Between Cuts To Prolong Step Bit Life, Rugged Case Snaps Shut With Custom Inserts For Each Bit And Oil Bottle, Total of 37 Hole Sizes