The Chef's Choice Model 1520 Angle Select Electric Knife Sharpener sharpens straight-edge and serrated knives, giving them a long-lasting edge in seconds. You can select sharp, hair-splitting edges or edges with varying amounts of "bite" for more demanding cutting. To form first and second bevels, Stage 1 is for German 20° angle knives and Stage 2 for Asian 15° edges. Stage 3 produces an ultra-smooth cutting edge with a revolutionary flexible stropping disk, like the familiar barber strop. Plugs into any AC outlet. Needs no honing oils or water. This professional electric knife sharpener is another sharpening breakthrough. It incorporates conical 100% diamond coated disks in Stages 1 and 2 and a revolutionary stropping/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.