Precision Self-Centering Drill Bit Precision Self-Centering Drill Bits are essential for pilot holes in hinges, handles, drawer slides and other parts, the taper that surrounds the drill bit ensure that the pilot hole is centered when countersinking the mounting hole, drill a pilot hole Sharp oblique edge at 135 degrees from the drill head, make the hinge drill faster in the position of the hinge holes. the guide that surrounds the bit is pushed by a spring to keep it in contact with the milling of the part to be repaired. Wood chips are automatically discharged Sawdust automatically flows out from both sides of the holes, no drill stuck, you don't need to remove the wood chips, effectively increasing your work Easy to use and clean install Wood of different hardness, need different centering drill, just disassemble the screw and replace the drill. Professional tutorials on how to use video will be provided. Product <br> Size: 4 Piece Self-Centering<br> Who is it designed for? <br> Mr. Do-it-yourself <br> - Professionals or hobbyists like carpenters, mechanics, cabinet makers, cabinet makers and other woodworking artisans. <br> - These self-centering pre-drill tips are ideal for pre-drilling holes for fixings, including hinges where having a perfectly centered pre-hole is essential. <br> - The 4 tips are of different sizes, to adapt to all models, from the largest to the smallest. <br> Single value: <br> 1. Provide professional video usage tutorials, please contact us <br> 2. Long-term durability: brass shell, high-speed steel drill bit, electroplating appearance, 14-month warranty <br> 3. Better punching performance: positioning accuracy, will not move, chips will automatically discharge from the hole on either side of the top of the drill bit and will not cause wood chip jamming problems <br> Size Common Instructions: <br> The 4 most common hinge screw sizes are 5/64