# 400 Grit Diamond Sharpening Stone This is perfect for flattening whetstones, and it allows for smooth and comfortable sharpening. If you continue to use a whetstone without flattening it, it will wear down and become uneven, preventing a proper edge from being formed. Therefore, it is necessary to flatten the surface regularly. ■ How to Use ■ Draw diagonal lines on the entire surface of the whetstone with a pencil, etc., and then water-sharpen with the diamond stone until the pencil lines disappear, resulting in a uniform surface. For the finish, sharpen lightly as if caressing the surface to achieve a more beautiful finish. Size: Approximately 152 x 63 mm ※ Please be aware of similar products that have unauthorized reproduction of our images and text. Our products are all inspected and adjusted before being described. ¥200 off when combined with other products. (Please request this in the comment section or using the bulk purchase function before purchasing.)