The drill bit is made of carbon steel and the countersink is made of high quality 45# steel, which ensures a long service life. The combination of drill and countersink is perfect for drilling, chamfering, deburring and countersinking There are 4 sizes: 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 10mm. Suitable for drilling holes in low hardness boards such as wood, plastic and other soft materials The five-wave design ensures small chip volumes and faster removal, allowing sawdust to be removed faster and more smoothly. Suitable for drilling holes with low hardness edges such as wood, plastic and other soft materials. The package includes: 7pcs x chamfer drill bits, 1 x Allen key