A shoulder sleeve insignia, (often abbreviated SSI) is an embroidered patch

Embroidered patch

An embroidered patch is a piece of art which is created by using a fabric backing thread and some form of a needle. Embroidered patches can be attached with a pin or can be sewn on, but some of the more modern methods of attachment include both an iron-on and Velcro backing...

 used by major formations of the United States Army

United States Army

The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...

. Each formation has a unique formation patch

Formation patch

Formation patches are types of military insignia developed during the 20th Century. Originally intended as battlefield identification of military formations, they have persisted into the 21stCentury as an element of military heraldry.-History:...

, and the US Army is unique among the US armed services in that all soldiers are required to wear the patch of their headquarters as part of their military uniform

Military uniform

Military uniforms comprises standardised dress worn by members of the armed forces and paramilitaries of various nations. Military dress and military styles have gone through great changes over the centuries from colourful and elaborate to extremely utilitarian...

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Shoulder sleeve insignia receive their name from the fact that they are most commonly worn on the upper left shoulders of all US Army uniforms, though they can be placed on other locations, notably a combat helmet

Combat helmet

A combat helmet or battle helmet is a type of personal armor designed specifically to protect the head during combat. Helmets are among the oldest forms of personal protective equipment and are known to have been worn by the Akkadians/Sumerians in the 23rd century BC, Mycenaean Greeks since 17th...

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