A whetstone is the best tool for Japanese style knife sharpening. The whetstone does not damage or scratch the knife steel and allows for the highest quality result when sharpening. Naniwa products belong to the top-class whetstones in terms of their sharpening properties. This 4000-grit whetstone is suitable for polishing knife blades. Naniwa products belong to the top-class whetstones in terms of their sharpening properties. The slide of the Standard (old name Traditional) series requires soaking in water for about 5-10 minutes before use. Dimensions: 210*70*20mm. Japanese kitchen knives generally have a sharpening angle of 15 degrees, European knives have a sharpening angle of 20 degrees. Before sharpening, read the sharpening instructions provided by the knife manufacturer. There is no need to clean or dry the stone during sharpening. If necessary, additional water can be sprinkled on the stone. After use, clean the whetstone under running water and dry it.