These drill bit sets include 6 individual drill bits. It is economical and easy to store. Titanium coatings are ideal for opening holes in a variety of materials. Stronger and more durable. The stepped design makes drilling and cutting accurate and efficient Convenient and widely used. New design, smoother cutting, make your industrial building more perfect. Connect the drill bit to the power drill Use another tool to measure the diameter of the desired hole size. Then select the step drill of the corresponding size Correctly install the step drill on the electric drill, and finally align the target hole position perpendicular to the workpiece, and start drilling to the required size. 1. Manual measurement, please allow 1~2cm error, thank you. 2. Due to the difference of different monitors, the picture may not reflect the actual color. Kind tips: In order to prolong the service life of the step drill bit and facilitate drilling, it is best to add oil before use. Color: Multicolor Size: 17*12*3.5cm Delivery quantity: 1 set