Carbide-Tipped Hole Cutter Kit. Contains 7/8", 1-1/8" and 1-3/8" cutter heads, pilot drill, hex key and case. Multiple tungsten carbide tips for long life and smooth cutting. Cut fast, accurate, high quality holes in stainless steel, copper, aluminum, steel. Flange stop prevents over-drilling. Replaceable cobalt steel pilot drill, with split-point tip design, to improve performance and resist walking. Eliminates need for center punch.