United States Marine Corps Collar Device (0-1) Pair is the official insignia for 2nd Lieutenant in the United States Marine Corps uniform. A Second Lieutenant of the Marine Corps is the first commissioned officer rank in the Marine Corps. They lead a platoon of 16 to 44 Marines including two or more squads led by a senior NCO. Official issue and approved by the US Institute of Heraldry. Comes as a miniature size, sold as pairs, and is made in the USA.