A powerful thunder-drum crafted by the Yellow Emperor (黄帝 huáng dì) from the skin of a Kui (夔 kuí), using their bones as drum sticks.
The drum is used by Lei Gong (雷公 léi gōng) to produce thunder.
In the battle between the Yellow Emperor and Chi You (蚩尤 chī yóu) it is said that the Yellow Emperor beat his Kui-Skin Drum to boost the morale of this troops whilst simultaneously making his enemies tremble with fear. It was a vital part of his victory.