15 Pfg medium lilac carmine with scarce watermark "steps falling" in mixed franking on about 1 Pfg postage exceeding tariff rate registered letter from "ZERBST - b - 23. 5. 46" to Hamburg with arrival postmark "Hamburg 11 -from 28. 5. 46", the stamp was lifted for checking and with hinge replaced, the additional franking fastened original, certificate with photograph Ströh BPP "genuine and immaculate" - very fine example of this rarity! (former starting price 400)