WW2 Polish Air Force Pilots Wing Miniature Silver Pin Bar

A good original circa 1940's period English Made 'Polish Air Force Pilot's miniature silver bar' well defined swooping eagle with laurel wreath in its beak, possibly converted from a gentleman's cravat pin and mounted on a pin bar, the reverse impressed 'Silver' the eagle marked 'Sterling'. Good condition, evidence of file marks to reverse. Width 49mm. Height approx 16mm.