Original US Army, WW2 era, shoulder sleeve insignia (SSI). The patch would have been worn on the shirts and jackets of US GIs who served in this unit.
We have a number of these available, so the one you receive may not be the one pictured. However, all have been carefully curated and none will be sent that show significant wear or damage. They may show light wear or use, but all will be suitable for display or for a uniform. We have a no-quibble swap guarantee if you're not happy with the one you receive.