SHARPAL 162N Dual-Grit Diamond Whetstone that measures L 8 inch x W 3 inch is capable of handling a wide variety of edges including kitchen and pocket knives with either a single or double bevel on the blade, tools and much more. With MirrorFlat™ technology, hard wearing surface and durable design, it guarantees consistent, even sharpening for years of dependable use. It is double-sided with both coarse and extra fine diamond surfaces. Use the coarse diamond stone 325 grit (45 micron) to quickly and easily restore a dull or damaged edge. Use the extra fine diamond stone 1200 grit (9 micron) to hone. Sharpen dry. No messy oil needed. It comes with a high-impact plastic self-storing case with non-slip rubber pad that can be used as a stone base while sharpening. More value-added gadget is the patent pending Angle Pyramid™ Sharpening Angle Guide integrated with 4 angles-14°, 17°, 20°, 25° for choice for almost all kinds of knives.