Our japanese cooking knives stay during a long time very sharp. Nevertheless, you may need to whet the blade from time to time. For this purpose you should regularly whet your knives with this fine ceramic rod-sharpener and your knives will always have the best sharpness. There is no easier way to keep your japanese cooking knives over years in best condition. The original japanese fine ceramic rod sharpener has a length of 180 mm and a very elegant ergonomic wooden handle.