|Drawing of a Zi Sheng Huo Chong, from 'Jun Qi Tu Shuo (《軍器圖說》)'.|
Wu Bei Yao Lue (《武備要略》) also mentions a special arquebus that is "faster and more convenient than both matchlock and flintlock", known as Fu Shou Ji (伏手機, lit. 'Hidden hand machine'), used by the peasant rebels. Ming army reverse-engineered the design, and named it Li Gong Guai (李公拐, lit. 'Master Li's crutch').