Chef's Choice EdgeSelect Diamond Hone No. 120. This professional electric knife sharpener is another sharpening breakthrough. It incorporates conical 100% diamond coated disks in Stage 1 and 2 and a revolutionary stroping/polishing disk in Stage 3 in just seconds, an edge of unprecedented sharpness and durability is obtained on fine edge (straight edge) and serrated knives. The flawless, highly polished fine edge can be customized to suit the cutting task. High-precision elastomeric angle guides eliminate all guesswork. 3 year limited warranty. White.