The Faithfull Hinge Boring Bit with a Tungsten Carbide cutter is designed for repetitive drilling of blind holes when fitting concealed (blum) hinges in kitchen, bedroom and bathroom cabinet doors. They are suitable for use on all natural woods and man-made materials such as blockboard, melamine faced boards, chipboard and MDF and provide a long working life.These bits should always be used with a stand-mounted drill.Features :Solid carbide tipped centre point Solid carbide main cutter Relief angle to reduce drag 5/16in - 8 mm shank