Outstanding Design: Unique design with perfect perforation effect. The saw will be automatically unloaded from the top of the holes on both sides, without stuck drilling. Easy to Replace and Install: According to the hardness of the wood, you can choose different center drill bits, disassemble the screw and you can replace the drill easily. At the same time, quickly change the bits that load and release with one hand. Multi-function: Drill for precise positioning, without movement. Applicable for the installation of the door hinge. Various Sizes: Includes 2 different sizes of 1/4", 5 mm hinge screws for carpenters, cabinets, furniture makers and other woodworking works. High-quality Material: Made of high-speed steel, with high hardness, rust-resistant, solid, durable and excellent for use.