The Shanghai Federation of Trade Unions was founded in 1925, and re-founded in February 1950 (after Liberation). It was given the Bank of Communications Building on the Bund, 14 East Zhongshan Road. That building is shown below left. The picture story, starting top left, is mostly about workers' resistance during the Second Sino-Japanese War and against the Guomindang.
This poster was issued as supplement to the union's magazine 劳动报画刊 - Labor Daily Pictorial nr. 15. Text and images are by Wen Cunxi (文寸西) and Hu Songya (虎松厓), but we do not know who did what.
More information, photographs and the announcement of an exhibition on the union's history are on the back: