What Is the Correct Way to Display O-6 Rank Insignia?
Question: U.S. Military FAQ What is the correct way to display O-6 rank insignia?
Answer: Both. An O-6 is a Colonel in the Army, Air Force, and Marine Corps, and a Captain in the Navy and Coast Guard U.S. (See our Military Officer Rank Chart).
O-6 "Eagle" insignia consists of a pair. On one insignia, the eagle faces the left, and on the other insignia, the eagle faces the right. This is because, when worn properly, the eagles are pinned on with the feet closest to the collar, and the head of the eagle turned to face toward the front of the officer's body.
The only way to accomplish this, on both sides, is to have "mirror" insignia (one opposite from the other).
This is clearly illustrated, for example, in Army Regulation 670-1, Wear and Appearance of Army Uniforms and Insignia, Figure 28-35 (Page 192). The eagle insignia which faces to the left is worn on the right shoulder (facing the front) and the eagle insignia which faces to the right is worn on the left shoulder (again, facing the front).