A dog tag, because of their resemblance to actual dog tags is the informal name for the identification tags, or ID Tags, worn by members of the U.S. Army, Navy, Air Force, Marine Corps, and U.S. Coast Guard. In the United States Military, the name, military ID number, branch of service, blood type, gas mask size and religion are stamped on a small piece of metal that is worn on a metal chain around the neck.
Each set of dog tags comes with two stainless steel tags on two chains, one long chain and one short.