Features Titanium Plated High Speed Steel: the drill bit is made of titanium plated high-speed steel with higher hardness and wear resistance 118° X type opening design: the drill bit adopts a 118° X type opening design, which can effectively prevent the bit from slipping Double spiral groove: this step drill bit with double spiral groove is not only convenient for chip removal, but also protects the cutting edge Easy to use: the step drill is easy to use, sawing and drilling, drilling and milling are dual-purpose, fast and efficient Wide range of applications: widely used for grooving, reaming and punching thin plates of wood, metal and plastic, etc. Feature: 1. Titanium Plated High Speed Steel: the drill bit is made of titanium plated high-speed steel with higher hardness and wear resistance 2. 118° X type opening design: the drill bit adopts a 118° X type opening design, which can effectively prevent the bit from slipping 3. Double spiral groove: this step drill bit with double spiral groove is not only convenient for chip removal, but also protects the cutting edge 4. Easy to use: the step drill is easy to use, sawing and drilling, drilling and milling are dual-purpose, fast and efficient 5. Wide range of applications: widely used for grooving, reaming and punching thin plates of wood, metal and plastic, etc. Specifications: Item Type: Spiral Groove Step Drill Bit Material: Titanium Plated High Speed Steel Shank Type: Hex Shank Step Drill, Round Shank Saw Drill 4mm-12mm Step Drill Bit: Blade diameter: approx. 4 mm / 0.16 inches, 6 mm / 0.24 inches, 8 mm / 0.31 inches, 10 mm / 0.40 inches, 12 mm / 0.47 inches. Total length: approx. 65 mm / 2.56 inches. Shank Diameter: Approx. 6.35mm / 1/4 inch 4mm-20mm Step Drill Bit: Blade diameter: approx. 4 mm / 0.16 inches, 6 mm / 0.24 inches, 8 mm / 0.31 inches, 10 mm / 0.40 inches, 12 mm / 0.47 inches, 14 mm / 0.55 inches, 16 mm / 0.0.0 63 inch 63 .18 mm / 0.71 inches, 20 mm / 0.80 inches. Total length: approx. 73 mm / 2.87 inches. Shank Diameter: Approx. 6.35mm / 1/4 inch 4mm to 32mm Step Drill Bit: Blade diameter: approx. Package List 1 x 4-12mm Spiral Grooved Step Drill Bit 1 x 4-20mm Spiral Grooved Step Drill Bit 1 x 4-32mm Spiral Grooved Step Drill Bit 1 x 3mm Saw Drill Bit 1 x 6mm Saw Drill Bit 1 x 8mm Saw Drill Bit 1 x Plastic Box