An authentic US Air Medal, post WWII manufacture with an interesting brooch on the reverse. I was unable to find an exact match ( a crimp brooch with a slot in the middle) online, but based on the quality of the award and the collection it came from, it is most likely a Vietnam era medal.

The Air Medal (AM) is a military decoration of the United States Armed Forces. It was created in 1942 and is awarded for single acts of heroism or meritorious achievement while participating in aerial flight.