Worn on both unit and personal awards, the “O” attachment is officially known as the Operational Distinguishing Device (ODD). As the name implies, the primary eligibility requirement for this device is that, regardless of the award with which it is being issued, both the work and unit the candidate are operational in nature. Simply being assigned to an operational unit of the Coast Guard does not mean the person is automatically eligible for the ODD device on a personal award. The opposite is also true: a Coast Guard member in an operational rating or specialty is not eligible for the device for duties carried out while assigned to a non-operational unit or if the personal award exclusively recognizes administrative achievements or service.
The ultimate factor in determining ODD eligibility, however, is how much the candidate directly participated in missions of a “hands on” nature; this is made clear in the regulations where it states that each case in which an ODD may be awarded must be judged on its own unique merits and that the citation must explicitly authorize awarding the device. Examples of operational missions include Search and Rescue, Aids to Navigation maintenance and operations, Fire Fighting, Maritime Law Enforcement, Disaster Relief, and Pollution Response. Again, simply being involved in such an operation will not automatically qualify a Coast Guard member for the ODD; the citation must clearly show how the candidate directly participated in operational functions and duties.
COMDTINST M1650.25 E,
Coast Guard Military Medals and Awards Manual, lists the personal and unit awards for which the “O” device is authorized to be awarded.
Personal
Unit
The "O" device is also used for wear on ribbons issued by the the United States Coast Guard Auxiliary. Personal awards eligible for the "O" device include the Coast Guard A
uxiliary Meritorious Service Medal,
Auxiliary Achievement Medal,
Auxiliary Commandant Letter of Commendation,
Auxiliary Recruiting Service Performance Award, and the
Auxiliary Operations Service Performance Award. The only unit award unique to the Coast Guard Auxiliary for which the "O" device is authorized is the Coast Guard Auxiliary Group Action Award.