Proof: 60 Kop. on 60 Kop. red as a single franking on marked registered cover "PSKOW 70" with cancellation "PSKOW -k -4 10 41" and as "arrival postmark" "-a- PSKOW -4 10 41", postal not transported, stamp in perfect condition condition, cover with some traces of usage, only issued 24 pieces!, signed Bartels, Dr. Schultz and certificate with photograph Zirath BPP (2014) : "this is a scarce proof where the only issued 24 pieces amounts. ", Michel 4. 200.-