For materials up to 3/16 in. this Milwaukee Quick Change Carbide Tooth Cutters for Sheet Metal (5 Piece Kit) (49-22-8300) produces fine, burr-free holes in a variety of materials. They are ideal for stainless steel, structural steel studs and electrical boxes. They can also improve your production in cast iron, brass, aluminum and other thin non-ferrous metals. These cutters are designed to be used in hand held drills to achieve drill press quality holes. The carbide tips stay sharper longer than high-speed steel or bi-metal cutters giving these cutters longer life.