High Quality Material: Carbon steel construction for high functionality and durability Wide Application Range: 1/4 inch, 5/16 inch, 3/8 inch, 1/2 inch, 9/16 inch, 5/8 inch, 3/4 inch, 7/8 inch, 1 inch, 1-1/8 inch, 1-1/4 inch, 1-3/8 inch, 1-1/2 inch, different sizes for different uses Quick Change & Hex Shank: 6mm hex shank with groove allows for quick loading of drill bits and prevents chuck slippage. It is compatible with most drills on the market Clean and neat: The precision-ground center tips for exact positioning and the channel for fast chip evacuation increase drilling speed and provide a clean cut Neat: It comes with a durable and portable storage box that is perfect for keeping your tools organized and carrying them to different workplaces 13pcs Spade Drill Bit Set Spade Drill Bit Set Material: Carbon Steel Shank Type: Straight Shank Length: 15 cm Diameter: 6 mm Sizes: 1/4 Inch, 5/16 Inch, 3/8 Inch, 1/2 Inch, 9/16 Inch, 5/8 Inch, 3/4 Inch, 7/8 Inch, 1 Inch, 1-1/8 Inch, 1-1/4