Sharpening stone featuring folding handle which protects the stone when not in use. Lightweight and portable with convenient key chain for keys, or to hook to bag or zipper. Coarse diamond, 45 micron/325 mesh, to quickly restore a neglected edge. Sharpen dry or with water. 5-1/2 In. opened, or 2-11/16 In. x 15/16 In. x 3/16 In. closed.