Reamer with Alternating Cutting Edges which work in continuous rotation, saving time and effort. Race system provides a solution to endodontic treatments, with a complete family of shaping and retreatment files. Material has the appearance of NiTi alloy and is flexible, extremely elastic, resistant and biocompatible. Elimination of screw-in effect for a reduced risk of instrument fracturing. Optimal cutting efficiency with rounded safety tip. Electrochemical polishing for enhanced resistance against fatigue and corrosion. Depth marks and slicone endo stop.