Shoulder sleeve insignia (SSI) are cloth emblems worn on the shoulders of US Army uniforms to identify the primary headquarters to which a soldier is assigned.
The SSI of some army divisions have become known in popular culture.
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Note: several insignia are of World War II formations.
Note: US infantry divisions were not formed under the following numbers: 53, 54, 56, 57, 58, 60, 64, 67, 68.