Description: Accurate positioning, will not shift, sawdust automatic discharge from the both sides of the hole on the top of the drill, will not be stuck. This product is used to open the hole of the hinge hole of the door and window, the drilling sleeve can fix the position well and ensure the accuracy of drilling. Cabinet door perforations, cabinet hinge positioning hole saws, woodworking tools, hinges for installing furniture doors, help drill center holes. Lightweight and portable, easy to operate, suitable for positioning and installation of furniture door hinges. When drilling, adjust the hardness according to the appropriate wood, if the wood soft, can choose a smaller size, if the hard wood, you can choose the corresponding larger one. Specification: Material: Aluminum Shell, High-speed Steel Core Size Chart: 17pcs: 5/64”, 7/64”, 9/64”, 5/64”, 11/64”, 5MM, 13/64”, 1/4” 21pcs: 5/64”, 5/64”, 7/64”, 7/64”, 11/64”, 9/64”, 9/64”, 5MM, 13/64”, 1/4” Package Includes: Optional: 1x Self Centering Hinge Drill Bit Set (17pcs) 1x Self Centering Hinge Drill Bit Set (21pcs) Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful on-line shopping!