Butterfly Sword

The butterfly sword (simplified Chinese: 蝴蝶双刀; traditional Chinese: 蝴蝶雙刀; pinyin: húdié shuāng dāo) is a short dāo, or single-edged blade, originally from the South of China, though it has seen use in the North.

The blade of a butterfly sword is roughly as long as a human forearm, which allows for easy concealment inside loose sleeves or boots, and allows greater maneuverability when spinning and rotating during close-quarters fighting. Butterfly swords are usually wielded in pairs. A pair of swords will often be carried side by side within the same scabbard, so as to give the appearance of a single weapon.

The butterfly sword has a small crossguard to protect the hands of the wielder, similar to that of a sai, which can also be used to block or hook an opponent's weapon. In some versions the crossguard is enlarged offering a second handhold, held in this position the swords can be manipulated in a manner akin to a pair of tonfa. They may also be used as brass knuckles when non-lethal application of the weapon is desired.

Traditionally, the blade of a butterfly sword is only sharpened along half of its edge - from the middle of the blade to the tip; this can be seen in all vintage specimens from the Qing Dynasty. The blade from the midpoint down is left blunt so that it can be used to deliver non-lethal strikes and to block without damaging the sharpened edge. Butterflies were generally commissioned for individual martial artists, not mass produced, so every set of swords is different, however an average blade today is about 11½" long with a 6" handle.