NOTABLE - FG Could be F6
The Special Collection Service (SCS), codenamed F6,[1] is a highly classified joint U.S. Central Intelligence Agency–National Security Agency program charged with inserting eavesdropping equipment in difficult-to-reach places, such as foreign embassies, communications centers, and foreign government installations. Established in the late 1970s and headquartered in Beltsville, Maryland,[2] the SCS has been involved in operations ranging from the Cold War to the Global War on Terrorism.
https://en.wikipedia.org/wiki/Special_Collection_Service