Ansen Tools AS-461 Grit Sharp 8 5/8-Inch Double Sided Diamond Whetstone Sharpener Coarse/Medium with a Non-Skid Rubber Base Double-sided coarse 220 grit-medium 500 grit with advanced monocrystalline technology Coarse diamond grit is ideal for a rough or uneven surface, while the medium diamond grit quickly smooths and sharpens a damaged edge Sharpens the toughest material including tool steel, carbide, titanium and ceramics Two stage sharpening ideal for cutlery knives, woodworking tools, gardening tools and machine tools The sharpener comes with a non-skid rubber base