Easy to Use: The hex shank design of our drill bit allows for quick and secure attachment to drills. It ensures stable drilling performance and reduces slippage during operation. No more hassle or frustration when working on your woodworking projects. Adjustable Cutting Depth: Easily adjust the depth of the flapper drill bits to fit the length of your screws. Simply tighten the pilot drill bit with the included hex key on the countersink/milling sleeve. Versatile Functionality: The drill is equipped with a 45# steel chamfering device, including an adjustable screw to control the drilling depth. This allows for efficient hole drilling while providing convenient chamfering capabilities. High Quality Material: Our hex shank countersink drill bit is made of 4241 high speed steel, ensuring its durability and longevity. The black chamfering part is made of 45# steel, providing excellent performance. Wide Application: Suitable for drilling in hardwood and plywood, our countersink drill bit