Patch, US Strategic Air Force
Genuine WWII US shoulder sleeve insignia of the US Strategic Air Force in Europe.
The United States Strategic Air Forces (USSTAF) was a formation of the United States Army Air Forces. It became the overall command and control authority of the United States Army Air Forces in Europe during World War II.
There is some difference of opinion about the USSTAF insignia/emblem. Most sources state the letters stand for United States Strategic Air Forces in Europe. However, there is evidence indicating – at least initially – it was United States Strategic & Tactical Air Forces.