50 H. Stamp exhibition Kaschau with hand stamp overprint "we are free! Plus swastika" in the vertical gutter pair, with special cancel "Liberec 1 German Reichspost eighth of October 1938 Heil Hitler! " on faultless blanko-envelope, edition 400 piece, of it few as gutter pair, photo expertize Brunel VP (2020) "the condition is perfect. Gutter pairs rare. ", Michel 300.-