In addition to its army, navy, and air force, the Soviet Union (USSR) had a Frontier Force to protect its borders. The color associated with its symbols was green, as in this ensign, displayed on all vessels and ships operated by the Force. The canton of the flag was the standard ensign of the USSR Navy; see collection item ZFC1106.

The distinctive Frontier Force ensign was introduced in 1935 and was replaced in 1992 by a post-Soviet design. This particular flag was reinforced in the corners.

These are often incorrectly called KGB flags. ZFC Noteworthy Flag
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