Shapton is one of the most reputable and highly-recommended whetstone makers in the world, and that's a testament to their quality. The Shapton Kuromaku series (often called "Shapton Pro" in the west) are versatile, professional-quality whetstones that are also suitable for beginners. This stone is one of the coarsest whetstones in the Shaptom Pro Kuromaku series. Coarse whetstones are designed for repairing and thinning blades. If you have a knife, planer blade, axe, pruner or other bladed tool that has bends or chips on its edge, or is very dull, a coarse whetstone like this is perfect to start with. After repairing the blade with this 320 grit stone, sharpen it with a medium (1000-1500) grit stone, and optionally polish with a very fine (5000+) grit stone. The Shapton Kuromaku 320 grit stone produces more slurry than other stones in the series, so it's good practice to rotate the stone with each use to ensure even wearing. Instructions: Soak the stone for 5 minutes before the first use. Soak for 30 seconds before subsequent uses (optional). Sharpen your knife on the stone, occasionally sprinkling water to keep the stone wet. Wash and dry your knife. Gently rinse your whetstone under clean water and air-dry completely before storing.