A tanto, nagasa measuring 23.6 cm, bearing the inscription 「吉光」 (“Yoshimitsu”) on the tang. The blade shows a straight hamon with slight undulation. While signed “Yoshimitsu,” the style and workmanship indicate it is likely a later attribution inspired by the famed Awataguchi Yoshimitsu of the Kamakura period.
Based on the workmanship and condition, the blade is estimated to date to the late Muromachi to early Edo period (16th–17th century).
The sword is mounted in excellent condition Imperial Japanese Navy large dagger fittings, featuring sharkskin-covered scabbard with gilt metal mounts, all parts matching and serialized. This style of mounting was reserved for naval officers, and its preservation adds historical significance to the piece.