3Pcs 3-12/4-12/4-20mm Multiple Hole Stepped up Bits for Metal Cone Hex Shank Hole

Description: Titanium coating reduces friction and heat. High-speed steel pedal drilling is of higher quality and durable than ordinary twisted drilling. These are perfect for creating smooth clean and round holes. Suitable for perforated metal iron aluminum brass wood plastic etc. This drill set includes 3 sizes (3-12mm 4-12mm 4-20mm) to meet your different needs. Black is treatment but a nitriding treatment to increase hardness and wear resistance. Size Chart: 3-12mm Total Length: 65mm/2. 4-12mm Total Length: 73mm/2.87inch 4-20mm Total Length: 77mm/3.03inch Package Includes: 3 Pieces Step Drill Note: Please allow 1-3mm measuring deviation due to manual measurement. Due to the different monitor and light effect the actual color of the item might be slightly different from the color showed on the pictures.Thank you!