The butterfly sword (húdié shuāng dāo) is a short dāo, or single-edged blade, originally from the South of China, though it has seen used in the North.
The blade length is approximately that of the forearm, for easy concealment within the sleeves or inside boots, and for greater maneuverability to spin and rotate in close-quarters fighting.
The butterfly sword is usually wielded in pairs.
The sword has also a small cross guard to protect the hands of the wielder, which can be too small to block or hook an opponent's weapon.
Butterfly swords are used in several Chinese martial arts, notably Wing Chun, Lau Gar and Hung Gar.
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