In the the United States Marine Corps Major is a senior officer, with the pay grade of O-4. Major ranks above
Captain and below
Lieutenant Colonel. Major is equivalent to a lieutenant commander in the U.S. Navy.
The insignia consists of a fanned cluster of gold oak leaves, although there are design differences between the Army/Air Force version and the Marine Corps version. The rank of major is considered the first field grade officer and warrants gold trim on the visor of the cap (silver trim for the USAF).
