WALNUT BITS: Steel taper drill bits are used for drilling holes in wood or other hardwood floors and are suitable for bench drill bits, impact drill bits, chuck drill bits, etc.It is an essential item for daily woodworking. STURDY AND DURABLE: Our wood drill bits are made of HSS steel with high hardness, good wear resistance and high heat resistance.The drill bit is ideal for drilling holes in wood, plastic, rubber, PVC and other materials. It is not a power tool and cannot be used for hard objects such as steel, ironand the stone. ADJUSTABLE LENGTH: The high speed steel taper drill bit kit includes an adjustable hex socket that can be adjusted by loosening and tightening the screws with a hex wrench.It can also be used to quickly remove accessories. QUICK CHIP VENTILATION: The hexagonal cone countersink drill bit features a chip flute and a three-sided chamfering machine that quickly discharges wood chips to achieve a smooth surface on any type of hardwood. DIFFERENT TYPES OF DRILLS: We have four sizes of wood drill bit with countersink, 6#, 10#, 13#, 16#.Model 6# corresponds to drill size 2.35mm, model 10# corresponds to 2.5mm, model 13# corresponds to 2.9mm, model 16# corresponds to 4mm and is equipped with a wrenchhexagonal of 5.5 × 2 cm.It is enough for your daily needs.