In 1913, the military launched the first generation of deck work clothes (it was stipulated that this kind of work clothes can only be used when it is necessary to work, and usually still wear sailor's clothes). The pullovers denim jacket (there are two patch bags under the chest). In 1917, there was no patch bag style, both coexisted. In 1918, there was a button closure jacket with a placket, or deck jacket, which coexisted. In 1922, the placket style has fully used to replace the previous pullover.