The chart below represents the current enlisted rank insignia of the United States Air Force. While all Air Force military personnel are referred to as airmen, it can specifically refer to the pay grades of E-1 through E-4, which are below the level of non-commissioned officers (NCOs). Above the pay grade of E-4 (E-5 through E-9) all ranks fall into the category of NCO and are further subdivided into NCOs (E-5 and E-6) and senior NCOs (E-7 through E-9); the term junior NCO is sometimes used to refer to staff sergeants and technical sergeants (E-5 and E-6).