Made from powdered high-speed steel. We recommend this high quality knife to professionals. This is not stainless, but made of high quality steel, and will not rust or lose its sharpness easily. Lifetime use is guaranteed with proper care. Sharpness will last more than any type of knives, however it will need sharpening eventually. It would be best to send them to Kirin Hamono, the manufacturing company, and have them sharpen. Kirin Hamono.co Postal code 915-0064 2-25 Aoba-machi Echizen-shi Fukui-ken Phone No： 0778-23-0031 When that is not an option because of fright costs, getting help from a professional is strongly recommended. Kirin Hamono was asked for permission to use their logo and name by Kirin Beverages, a famous beer manufacturer in Japan, and they did permit. That was quite a long time ago, and that is the reason the logo is the same as shown in one of the pictures above. So this makes them an original, not the other way around.