Flag of the Prime Minister of the Kingdom of Italy first used in 1927 during the Fascist era in which Benito Mussolini served as Prime Minister, under the official title of "Head of Government and Duce of Fascism" from 1925 to 1936, and then "Head of Goverment, Duce of Fascism, and Founder of the Empire" from 1936 to 1943. The flag was used until 1943, when Fascism was banned in Italy.
Own work based on: Flag of Mussolini as Capo del governo of Fascist Italy.svg by R-41 and F l a n k e r

The exact form of the flag can be seen on images from Mussolini's visit to Hitler in 1937 here and here, in a less precise quality here.
The waving flag can be seen at an Video from Mussolini's visit to Tripoli (Libya) in 1935 here at 00:01.
The colors can be seen at an colored newspaper image from Mussolini's speech in Berlin (1937) here.
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