KUIBIS, black rubber handstamp with travelling postmark I of 15.5.07, ideal clear nearly central strike on correct-rate registered cover with 40 Pfennig to Wiesbaden, Germany, arrival mark, provisional registration label No. 24 with manuscript "Kuibis". Only 3 correct-rate registered covers with this cancellation known to date, perfect condition, unsigned, photo certificate Czimmek BPP (1995) "in the very finest condition. The rarity must be particularly emphasised.", ex Berker collection.