General description Self-centering hinge drill bit set allows for quick bit changes without the need for rechecking tools. It is perfect for hinges, handles, drawer slides, and woodworking projects. Technical specifications Includes 16 pieces: 8 center drill bits and 8 replacement drill bits Center drill shank diameter: 6mm Drill bit sizes: 5/64", 7/64", 9/64" (x2), 11/64", 13/64", 5mm, and 1/4" 135° bevel blade drill Installation Prepare a center drill and an Allen key Insert the Allen key and turn it Grasp the top of the drill bit and unscrew the shell Assemble the parts Usage Adjust drilling speed according to the hardness of the wood For soft wood, use a smaller center drill bit For hard wood, use the corresponding or larger drill bit If the center drill bit gets stuck, use the Allen wrench to separate it Other information Package includes: 8 NatureAqua Center Drill Bits, 1 Hex Key, and 8 Replacement Drill Bits