Precise positioning, no displacement, chip will automatically pass through the hole on the front side of the bit without sticking the bit Used for the door and window hinge screw hole opening, drilling sleeve can be very good fixed position, to ensure the accuracy of drilling This exquisite design, powerful function, whether it is woodworking DIY or engineering use is a durable tool When opening the holes, please adjust them according to the hardness of the wood. If the wood is soft, you can choose a smaller size. If the wood is hard, you can choose a larger size