The United States Army Air Force service cap was the stand uniform cap issued to all American soldiers. Many pilots and crew members removed the hat ring to give their service caps the "crushed" look.
This service cap was worn by the donor, 1st Lieutenant John Nagay. Nagay served as a B-24 Bombardier and Navigator in the 15th Air Force from September 1943 to March 1944 and was wounded by Flak over the Anzio beachhead in February 1944.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.