Just on my first search I found httpwwwdefenselinkmilspecialsinsigniasofficershtml In general no pun intended the US military refers to all generals and admirals as flag grade officers all of them have flags associated with their rank and branch of service The remaining grades of officers are company grade O through O this translates to Lieutenants in the Army Air Force and Marines and Ensigns and Lieutenants in the Navy and field grade O thought O Majors Lieutenant Colonels  Colonels in the Air Force Army  Marines and Lieutenant Commanders Commanders and Captains in the Navy