Kasumi Knives are produced by the Sumikama Cutlery factory in Seki Japan. Sumikama specializes in producing knives from the most advanced materials, with the most advanced manufacturing techniques. Kasumi Sharpening Accessories are designed specifically for use with Kasumi knives, but can be used for any Japanese knife brand. Always follow the sharpening instructions on the packaging. Professional ceramic whetstone - soaking is not required The deluxe whetstone is coarse (Grade 440) on the one side for edge restoration The fine side (Grade 1000) for finishing off the edge to a razor's finish A rubber base to hold the whetstone and prevent slippage is included Use this sharpener with your Kasumi brand knives, and any other slim Japanese style blades Made in Japan