This sword was used by Ryūgan in an anime-only filler arc in Part I. The sword has a metal wire passing through the blade. This wire controls it's movements as the blade can expand and be shot after the targeted enemy. Also, each of the swords blade has the ability to react to the carrier's chakra, amplify it and change its form to that of a dragon.
"Weapon" is not in the list of possible values (ANBU, Cooking-nin, Daimyō, Hunter-nin, Jinchūriki, Pseudo-Jinchūriki, Medical-nin, Missing-nin, Ninja monk, S-rank, Sage, Samurai, Sannin, Sensor Type, Summon, Tailed Beast, Mercenary Ninja) for this property.