Chef’sChoice 250 Diamond Hone Hybrid Sharpener Combines Electric and Manual Sharpening for Straight and Serrated 20-degree Knives Uses Diamond Abrasives for Sharp Durable Edges, 3-Stage, White 3-stage sharpening and our advanced hybrid technology are combined in this compact, easy to use sharpener that features both electric and manual stages and 100-percent diamond abrasives to quickly apply a super sharp, arch shaped edge. Ideal for all quality knives including fine edge and serrated, kitchen and household as well as sports and pocket knives, the m250 creates a triple bevel edge using three successive stages. The first and second stages are electric and use 100-percent diamond abrasives for shaping and sharpening the first two edge bevels. Stage 3 hones and polishes the third bevel using ultra-fine diamonds for a razor sharp, arch-shaped, professional edge that is stronger and more durable than conventional v-shaped or hollow ground edges. Since it is the manual stage, stage 3 can be used anytime and anywhere without power. It also sharpens serrated edges. One year limited warranty. Engineered and assembled in the u.s.a.