Made from Carbides,which makes cutting sharper,unhindered chip removal and with excellent drilling ability and excellent drilling. It is head adopt curves double-edged designs,quick waste removal and ensuring that you work efficiently. Create perfectly round and accurate holes with the middle track designs. The middle of each chisels accurate drilling and prevents walking and wobbling during. Wide ranges of uses: suitable for drill,benchs drill,vertical drill,hand drill,motor-driven stand drill and magnetic tape drill with mobile tape,.Can be used for perforation of wood product,mounted doors,tip,drawer,product,.