They are also worn on the right sleeve by soldiers to indicate former overseas service with certain units during periods of U.S. military operations in hostile conditions (MOHC).

However, with the retirement of the Army Green Uniform in 2015, the full-color SSI was discontinued and was replaced with a CSIB (combat subdued identification badge).

"Full color" SSI were only worn on the brown service coat during the 1940s, and on the green "Class A" uniform and on the OG-107 during the late 1950s and early 1960s.

Formerly, full color SSI were also worn on the "full color" (white letters on black or dark blue material) Military Police brassard, worn by MPs while wearing the green "Class A" service uniform or while wearing subdued field uniforms (BDU or DCU) in a garrison environment.

In one notable exception, the U.S. 1st Infantry Division wore full-color SSI on their BDUs and ACUs for a time, before that too was replaced with a subdued version.

These SSI are primarily foliage green, light brown, and black, though a few patches also feature red and maroon colors for some details.

Unlike previous patches, the ACU SSI are velcro-backed, designed to attach to the velcro pockets on the shoulder of the uniform, instead of being sewn on.

The most common place for the SSI to be worn on the ACU is on the upper sleeve, attached using a velcro backing; however, it is also sometimes worn on other places, notably when the soldier's body armor covers the shoulders, such as the shoulder pads of interceptor body armor, which covers the upper arm.

Early in the Global War on Terrorism, soldiers could earn the wartime service patch of several units during a single deployment according to their chain of command.

In actuality, the regulation states that soldiers will wear the shoulder sleeve insignia of former wartime service of the lowest deployed echelon authorized its own distinctive SSI, which applies to divisions, separate brigades, and a handful of battalions.

After March 27, 2007 the policy was changed to allow units of company level and higher to wear the SSI of their regular headquarters as a combat patch.

When men of the other fighting divisions challenged the right of 81st soldiers to wear the patch, General John J. Pershing ruled that the 81st could keep this distinctive insignia.

Subdued patches and insignia were introduced during the Vietnam War and were made mandatory for wear on the field uniform starting July 1, 1970.