Forstner drill bits create flat-bottomed holes, ideal for installing concealed hinges commonly found on most cabinets in the home. They are able to drill through softwood, medium hardwood, chipboard and MDF. Manufactured from high-strength carbon steel, the bits are tungsten carbide tipped and have twin cutting edges and quad spurs for fast waste removal and clean cutting. The drill bits are compatible with drills with the standard 10 or 13mm chuck. The five-piece set comes supplied in a wooden storage box.