WOOD DRILL BIT KIT- It comes with 8pcs wood drill bits, a hex key and a storage box. The wood twist drill bits are 3mm(2pcs), 4mm, 5mm, 6mm, 7mm, 8mm, 10mm, enough to meet your varieties of needs. DURABLE & STURDY- Our wood drill bit is made of HSS steel, high hardness, good wear resistance, high heat resistance. Perfect for drilling in wood, plastic, rubber, PVC and other materials, not a power tool, can not fit hard things like steel, iron, stone. USAGE- The wood router bits are used for drilling on wooden floor or other hardwood, suitable for bench drill, hammer drill, drilling machines with chuck and more. QUICK CHIP DISCHARGE- The wood twist drill bits have the chip flutes and five-edge chamfering machine, can discharge sawdust quickly to get a smooth surface on any kind of hardwood. ADJUSTABLE LENGTH- The wood router bit kit comes with a hexagon sleeve which is adjustable, to adjust the various length screws by loosening and tightening the screw. can also be used for