17PCs Self Centering Drill Bit Set Hex Shank Self Center Hinge Drill Bits Tool for Woodworking Features: 【】 steel self centering drill bits with high hardness, which is rustproof, solid, and superior drilling performance which is guide for centering the pilot holes needed for the hinges. 【Reasonable Design】 Double-sided hole design fast and automatic discharge sawdust from the hole on both sides, without drill blocked, which helps you save time in removing sawdust. 【Easy e and Install】 Different hardness wood, need different self centering drill, you just use the hex keys take the screw apart and replace the drill with new one. Perfect carpenter tool for woodworking, wooden doors, cabinets, windows, etc. 【Widely Used】 Applicative for furniture, kitchens, woodworking, window door etc. It can be adjusted appropriately according to the hardness of the wood. If the wood is soft, you can choose the smaller one, if the wood is hard, you can choose the corresponding one or the larger one. 【Product Dimensions】 Hinge drill bit set comes with 8 colorful common hinge screw sizes 5/64", 7/64", 2 x 9/64", 11/64", 13/64", 1/4", 5mm; 1pcs hex keys, 8pcs spare drill bits, 1pcs storage box.    Tips:  Use low speed when drilling (usually keep in 2000r/min to 3000r/min). Too fast speed will off center, break the bit or jammed Specifications: Color : Colorful Material: Alloy Steel  Shank Type: Hex Package Weight:340g / 11.99oz Package Size: 16*15.2*1.5cm / 6.3*5.9*0.59in Package List: 8 * Self Centering Hinge Drill Bits 8 *  Drill Bits 1 * Hex Keys 1* Storage Box