A twist drill is a tool that cuts a round hole of a workpiece by rotary. It is named after its flute shaped like a spiral. Twist drills can be used in manual, electric hand-held drilling tools, milling machines, lathes and even machining centers. The bit material is generally a high speed tool steel or a hard alloy. Features: 1. Suitable for aluminum, wood, malleable and deep hole drilling positioning holes iron. 2. Through heat treatment, stainless steel, tool steel, and other workpiece that are difficult to process, can be processed by these twisted drill bits. 3. High speed steel to obtain high hardness, high wear resistance and high toughness. 4. Can be used in manual, electric hand-held drilling tools, milling machines, lathes and more. 5. Sharp twisted drill bits will make the drilling easier and more effortless. Specifications: Material: High speed steel Surface Treatment: Titanium plating Handle: Hexagonal handle Quantity: 13pcs Diameter: 1.5mm, 2mm, 2.5mm, 3mm, 3.2mm, 3.5mm, 4mm, 4.5mm, 4.8mm, 5mm, 5.5mm, 6mm, 6.5mm Weight: Approx. 167g Package Includes: 13 x Twist Drill Bits