Marine Corps Master Sergeant Rank Gold Pair is the official United States Marine Corps rank insignia for Master Sergeants. A Master Sergeant is a senior enlisted advisor that is given the duty of being in charge bringing together enlisted Marines and their commanding officer. Master Sergeants are held in high rank for they have a complete overview of tactical training and strategy. This gold pair is the official issue for the United States Marine Corps uniform. This insignia measures at ⅞ inches and is made in the USA.