3 Kc. Airmail with overprint "Karlovy Vary 1. X. 1938 plus swastika", neat cancelled Karlovy Vary 1 4. X. 38 4 d on piece, issued only 25 examples - one of the large rarities the Sudeten territory philately, expertise Robert Brunel VP (2019) "the condition is perfect. Very rare", Michel 1.900.-