Posthorn 1951, X+20 Pfg, vertical se-tenant, from margin of sheet with bar of dashes as unit with vertical se-tenant 10 Pfg+20 Pfg, cancelled \"Wiesbaden 5 9.5.54\", faultless condition, rare, unsigned, photo expertize H. D. Schlegel BPP (2022) : \"the quality is perfect. \", Michel 740.- - rare in this quality offered!