Shoulder sleeve insignia (SSI) are cloth patches worn on the shoulders of US Army uniforms since World War I to identify the primary headquarters to which a soldier is assigned. Insignia is issued to commands, field armies, corps, divisions and brigades. Some other formations also have SSI's and rarely - a regiment may have one. They are created and assigned by the US Army Institute of Heraldry. When a unit is deactivated, so usually is the SSI, but it can be reassigned. Also an SSI can be deactivated and the unit will then usually wear the insignia of its next highest command (usually a division or a command). [1] [2] [3]
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