Adjustable Drilling Length: can be adjusted for different screw lengths by simply loosening and tightening the set screw. Premium Material: made of alloy steel. It is very suitable for drilling holes in wood of various sizes. A versatile tool that improves work efficiency. Application: Compatible with drills with chuck, for drilling in wood or parquet, for DIY, home and general construction or technical use, etc. Efficiency: the spiral flute with a center drill will quickly remove chips from the hole, the five-edged chamfer design effectively prevents debris accumulation and improves drilling efficiency. Stored in a package sealed with good protection. Especially used on metal and steel plate, provides fast and easy cutting. Suitable for woodworking. Drill and countersink for wood screws without changing bits. Counterbore adjustable in depth with an Allen key. 1. Check the integrity of the hole opener before use and tighten the hole insert when loading the drill. 2. When working, the hole opener should be perpendicular to the workpiece. 3. After positioning, the driving force is slightly given during the drilling process. 4. When drilling, the rotational speed should not be too low, which prevents the blade from sticking and causing chipping. 5. Coolant should be added during the opening process to prevent damage from excessive temperature. Delivery quantity: 5 pieces, (Package contents: Only the above package content, excluding other products.) Size: The detailed size is shown in the picture (Reminder: The size is measured manually, please allow 1-2 cm measurement error) Color: orange (Due to different monitors and lighting effects, the actual color of the item may be slightly different from the color shown in the picture.)