The AAV-7A1 AMTRAC, better known as the Amphibious Assault Vehicle, or simply AAV, is a tracked armored personnel carrier used by the United States Marine Corps and it is built by US Combat Systems, a subset of BAE Systems Land & Armaments. "AMTRAC" is a contraction of "amphibious tractor." The AAV has been in service with the United States Marine Corps since 1972 and is used by ten nations worldwide since its introduction.