Katana signed and dated by Sadayoshi, a smith of the Tsukushi Ryōkai branch: according to the original seller, part of the Kyoto Ryōkai school settled in Kyūshū and flourished throughout the Muromachi period, producing several smiths who share the character "yoshi". The tang, ubu according to the seller and intact in appearance in the photographs, with kiri file marks, a kurijiri tip and two mekugi-ana, bears on the omote 了戒貞能作 (Ryōkai Sadayoshi saku) and on the ura the date 天文十五年十二月吉 (Tenbun jūgo-nen jūni-gatsu kichi). The blade is shinogi-zukuri with iori-mune and chū-kissaki, 70 cm in nagasa with 2.8 cm of sori; long for its time, broad and thick, with pronounced saki-zori: the silhouette of the Sengoku era. The photographs show a bōhi on both sides, which the seller describes as running kaki-tōshi into the tang. According to the original seller, the jigane is tight ko-itame mixed with itame and shirake-utsuri, and the hamon a tight nioi chū-suguha with ko-ashi, yō and hotsure; the bōshi is straight with ko-maru. Double habaki in copper with gold foil. The blade is kept in shirasaya, without mounting. NBTHK Tokubetsu Hozon Tōken paper issued in 1999; the photographs also include a page from the book 大分県の刀 (Ōita-ken no katana) with the oshigata of this blade.