Dog tag (identifier)

A dog tag is the informal name for the identification tags worn by military personnel, because of their resemblance to actual dog tags. Various formats exist around the world but in the US Army dog tags record the surname, given name, social security/service number, blood type and religion - stamped on a small piece of metal that is worn on a metal chain around the neck. During World War II, certain medical information such as the date of the soldier's last tetanus shot was also included on the tag. The tag is primarily used for the identification of dead and wounded. In the event the member has a medical condition that requires special attention, an additional red tag with the pertinent information is issued and worn with the dog tags.

Wearing of the tag is required at all times by soldiers in the field. It may contain two copies of the information and be designed to break easily into two pieces. This allows half the tag to be collected for notification while the other half remains with the body when battle conditions do not allow the casualty to be immediately recovered. Alternatively, two identical tags are issued. One is worn on a long chain around the neck; the second on a much smaller chain attached to the first chain. In the event the wearer is killed the second tag is collected and the first remains with the body.