The Ming and Qing Dynasties were the peak of the development of Chinese martial arts. Hidden weapons were developed during the Qing Dynasty. The Qing Dynasty was the last imperial dynasty of China, ruling from 1644 to 1912. This Sleeve Arrow was one of the most popular tool-driven hidden weapons. These have been featured in the National Geographic special on “Top Ten Kung Fu Weapons of China.” Mechanical concealed weapons are #4 on the list. Jump to 23:45 min.
(Source Video Embed Code from National Geographic)
It is referred to as the sleeve arrow because it would be hidden in the sleeve of a chaofu or bufu robe, then as a stealthy kung fu master approached the victim he would aim and press down on the safety to take the victim out. The copper barrel of sleeve arrow is hollow with a spring inside. The tip of the arrow was dipped in poison before being inserted into the barrel.