Military Op codes >
http://www.icd10data.com/ICD10CM/Codes/V00-Y99/Y35-Y38/Y37-
United States military occupation code, or a Military Occupational Specialty code (MOS code), is a code used in the United States Army and United States Marines to identify a specific job. In the U.S. Air Force, a system of Air Force Specialty Codes (AFSC) is used. In the United States Navy, a system of naval ratings and designators is used along with Navy Enlisted Classification (NEC) system.
ARMY: The MOSC is typically a nine-digit code for Army Personnel, and is used for personnel classification above a job specialty. The first three characters: two numbers followed by a letter. Typically the first two numbers give away what field and rank each member has earned.
MARINES: The MOS is typically a 3 digit code for Marines, with the first two numbering from 01-99, giving their occupational fields, with the last digit for their specialty.
NAVY: Called NEC, Naval Enlistment Classification, by providing ratings by a two or three digit code. Naval Officers use a “Designator”.
COAST GUARD: Uses an MOS similar to the Army and Marines. They divide theirs up by groups such as Administration, Aviation, and Scientific.
AIR FORCE: Uses a five digit code for AFSC, Armed Forces Specialty Code for enlisted airman, and a four digit code for officers.