Silver O Device
Criteria: The silver Operational Distinguishing Device or "O" Device is a decoration of the U.S. Coast Guard that is worn as an attachment to specific awards including the Coast Guard Unit Commendation, the Meritorious Unit Commendation, the Coast Guard Commendation Medal, the Coast Guard Achievement Medal, and the Commandant's Letter of Commendation Ribbon. The decision to award the "O" Device is made by an award approving authority and is based on meeting the criteria of personal and unit participation directly in a mission of operational service.
The "O" Device is worn either centered on the award ribbon, or middle-right if there is an even number of devices worn on the ribbon. One "O" Device is worn per award ribbon.