Wrapping the handle and the sheath with a thin metal plate in a spiral is called hirumaki, which was used for reinforcement and decoration purposes. The hirumaki sword is a type of koshirae (outer fittings) that was popular among samurai. For the handle, the bronze ground is plated with silver and wrapped with a cloth, which is coated with lacquer and over which metal fittings with a lion pattern are mounted. The sheath is lacquered in black and wrapped with silver and copper plates in three stripes (komochihirumaki) and the ashiai is lacquered and wrapped with a cloth in diamond (watarimaki). The kabutogane, fuchigane, semegane and ishizuki are made of silver and copper without any pattern. The tsuba (handguard) in the shape of mokko (platycrater) is lacquered in black and rimmed with a copper band. It is said that Nanbu Masanaga (? to 1360) used to wear this tachi.