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 Richard Morris, who served as B-17 pilot in the 8th Air Force, 92nd Bomb Group, 326 Bombardment Squadron, from January 1945 until the end of the war.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.