The new Chef's Choice Trizor XV Sharpener is another breakthrough from the world's leading manufacturer of quality knife sharpeners. With ultra-sharp EdgeSelect technology and the stability of a triple bevel (Trizor) edge, you can hone your knives to a high performance 15 degree angle. The three stage process and efficient flexible stropping disks sharpen the edge with minimal metal removal, helping to extend the life of fine knives. Diamond abrasives on the conical disks in Stage 1 create extremely fine micro- grooves (for more bite), while simultaneously creating the first major bevel of the arch shaped edge. Stage 2 uses even finer diamond abrasives on conical disks which shape the second, smaller bevel with finer microgrooves. Stage 3 uses the patented flexible abrasive stropping disk system to create a microscopically smooth, sharp edge. It creates the third and final bevel while polishing the micro-grooves formed in stages 1 and 2. Stage 3 is also used to sharpen serrated knives, as it straightens and sharpens each tooth.