The flag of a Soviet voluntary sports association, the Central Sport Club of the Army, founded in 1923/1953 and based in Moscow. It features a red field with a blue wedge/chevron at the hoist, defaced by a red star outlined in gold, itself defaced by the letters of the initials of the club. Image here based on this: http://ogeraldike.ru/books/item/f00/s00/z0000007/pic/000043.jpg. See also: https://www.crwflags.com/FOTW/FLAGS/su@.html#cska. For information on the club: http://eng.mil.ru/en/index/social/sport/cska/more.htm?id=8716@morfOrgSport
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