It is based on the common left breast pocket work shirt from 1930 to 1950's.
old time shirts were pocketless. In the 19th century, with the development of industrialization in western countries, there were huge numbers of workers in different fields and different kinds of workers. The shirt that was once used as underwear or dress was no longer suitable for the workers, so the functional design of the pocket appeared on the left breast of the shirt (because most people are right-handed). For different types of workers will have different needs, gradually multiplied bag cover, double pockets and other various functional design.
6oz Stripe jacquard yarn-dyed fabric, 100% cotton, made in Japan