Ansen Tools Grit Sharp AS-417 Premier Fold-Up Double-Sided Diamond Whetstone Sharpener Coarse/Fine Double-sided (Coarse 300 grit - Fine 600 grit) each side with monocrystalline advanced technology The coarse diamond surface will quickly sharpen a damaged or dull edge and the fine diamond surface will bring back a razor sharp edge Compact and lightweight, the handles fold to protect the diamond whetstone sharpener when not in use Sharpen dry or with water Ideal for the toughest materials. Will sharpen all types of cutlery knives, woodworking tools, garden tools and machine tools