Item description from the seller Electric Knife Sharpener Rechargeable for Straight & Serrated Knives Sharpening, 2-Stage Polishing, Sharp Edge, Kitchen Tool, USB Charging, Diamond Steel . The Sharpener is a two-stage rechargeable sharpener which quickly and easily sharpens almost any fine edge blade. Get professional cutlery results in the convenience of your home. Engineered to both hone and polish simultaneously, the knife sharpener machine brings sharpness back to even your dullest knife blades. All you have to do is insert your blade into the slot and press the power button to revitalize your knives!.