Features: Accurate positioning, no displacement while use, and sawdust will be automatically discharged from the holes on both sidee of the drill, and the drill will not be stuck. Consists of copper housing, high-speed steel core-bit, and electroplating appearance, efficient drilling without burr. Mirror plating anti-rust process, beautiful appearance, comfortable griping feeling, and can provide long service time. Equipped with chip removal holes, which can speed up the chip removal, the wood chips are not blocked, improve work efficiency. Professional drilling tool pplicable to the installation of door hinge, 4 different sizes (5/64inch, 7/64inch, 9/64inch, 11/64inch) suit most use. Note: When opening the hole, you can choose the specifications according to the hardness of the wood board. If the wood is soft, you can choose center drill with a smaller opening diameter. If the wood is too harder, you can choose the corresponding size or a larger one. Specifications: Name: Hinge Holes Opener Material: copper + high-speed steel 5/64inch: Hole diameter is about 2mm, Use about 2.2-2.8mm tapping screw 7/64inch: Hole diameter is about 2.8mm,Use about 3-3.5mm tapping screw 9/64inch: Hole diameter is about 3.5mm,Use about 4-4.5 mm tapping screw 11/64inch: Hole diameter is about 4.5mm,Use about 5-5.5 mm tapping screw Length: 5/64inch: 85mm / 3.35in 7/64inch: 90mm / 3.54in 9/64inch: 95mm / 3.74in 11/64inch: 100mm / 3.94in Package size: 100 * 50 * 50mm / 3.94 * 1.97 * 1.97in Package weight: 99g / 3.49ounce Packing List: 4 * Hinge Holes Opener 1 * Wrench