For materials up to 3/16 in. these Carbide tipped sheet metal cutters produce 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. Lubrication during drilling extends the life of the Carbide cutter. Milwaukee recommends the use of Hawg wash cutting fluid for best results. Hawg wash fluid is available in 16 oz. Bottles (49-32-0081). One bottle makes one gallon of lubricating solution. Arbors 49-57-0035 or 49-57-0037 are needed for these cutters.