SEKIMAGOROKU KAI Diamond Ceramic Sharpener for Kitchen, Single Edge AP0162 Three different types of whetstones with different properties are included in a single unit, and by using them in turn, you can easily revive the sharpness of dull kitchen knives.. ●This product is exclusively for single-edged kitchen knives such as de-edged knives and sashimi knives. ●It is very convenient for daily use because there is no need to adjust the angle by yoursel, and it is easy to handle. It can be used for Father's Day, Mother's Day, retirement gifts, wedding gifts, birthday gifts, and housewarming gifts!