Sadatoshi was a swordsmith who lived in Ayanokoji, Yamashiro no Kuni. Old documents on swords say that he actively produced swords in the Bunei era (1264 to 1275). However, the style of his existing swords suggests that he was a swordsmith of an earlier period. This tachi (a sword made to be worn with the cutting edge down) has become shorter and slim due to later grinding. Compared to Sadatoshi's other swords, this one has a clearer jigane (ground metal) and hamon (blade pattern) with a more organized kochojiba (a small clove pattern).