The ultimate combination of sharpening stone and file! 100% diamond abrasives sharpen or shape any material. Puts a razor-sharp edge on any alloy knife, even tungsten carbide tools. Tackles your toughest filing jobs: ceramic tile, hardened steel, glass, concrete and more. Files on both pushing and pulling strokes. Three 100% diamond abrasive pads are available -- coarse, medium, and ultrafine - which interchange quickly and easily on the DualTrak MagneLok magnetic holder. Made in the U.S.A.