The senior noncommissioned officer in a company or squadron indicated by three chevrons and rockers with a diamond (lozenge) between chevrons and rockers. The pay grade is E-8 and is the same in the Army. In the Navy and Coast Guard, the rank is senior chief petty officer with a star above the eagle. First sergeant in the Air Force is a billet and is indicated by a lozenge between chevrons and rockers on any insignia between master sergeant and chief master sergeant.