At Sanjo-Seisakujo in Nigata, Kosuke Iwasaki began the production of Kamisori, in addition to his work in metallurgical research, which was then passed to Shigeyoshi Iwasaki, and currently to Ryouichi Mizouchi. Kamisori currently produced have a hagane(cutting edge) of Swedish high carbon steel. The finger rest on Iwasaki kamisori are all hand ground on the side of the wheel. Iwasaki are the benchmark for Japanese razors, and many smiths in the Sanjo region have at one time or another have been under the tutelage of Iwasaki-san in some form.