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 " long with a 6" handle.