Greenlee 625-1-3/8 Carbide-Tipped Hole Cutter, 1-3/8-Inch 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 a center punch