Special highlight: • Durable and practical • Ideal for the wooden plank, fiberboard, particle board, plywood, plastic, aluminum board ,etc. • Suitable for DIY, home & general building/ engineering using Function: • To chamfer or bevel the edge of a drilled hole such that a countersunk head screw can be seated flush with material surface. Package include: o 6mm (x1) o 10mm (x1) o 13mm (x1) o 16mm (x1) o 19mm (x1)