Army - Sergeant First Class - Retired Italic V1 Classic T ShirtSolid colored t shirts are 100% combed ringspun cotton, however, heathered colors could contain a cotton polyester blend Preshrunk to minimize shrinkage Double needle sleeve and bottom hems. Sergeant first class replaced the rank of technical sergeant in 1948. (However, the U. S. Air Force, which separated from the Army in 1947, retained the rank of technical sergeant and the U. S. Marine Corps had the rank of technical sergeant until 1959.)