HIGH SPEED STEEL STACK - Made with high speed steel, this cutter is able to cut multiple layers of material sumultaneously at a high level with maximum strength MULTIPLE LAYERS CUTS - Use to simultaneously drill multiple layers of steel, copper, aluminum, sainless steel, and plastic FAST, ACCURATE HOLE CUTTING - Quickly, accurately and safely cut large holes in steel up to ten times faster than standard twist drill bits IDEAL FOR DIFFICULT CUTS - Cutting profile provides unique functionality; use to make overlapping holes, slotting holes and edge cuts PILOT PIN INCLUDED - Included for easy plug ejection as well as marking cutting points, the Pilot Pin makes the job even more efficient and seamless Made with unique teeth profile, these Euroboor HSS Stack Annular Cutters are made to drill multiple layers of material simmultaneously. Also used for single layer work, the cutters create precise and clean hole finishes with the time savings you need on the job.