Heinrich Köhler 383rd Auction – Day 5 Germany 1849–2000 – German Empire, German Colonies with Occupation Issues (G.R.I. and MAFIA), Plebiscite Areas, Germany after WWII – The Erik B. Nagel Collection (part III)

1920, 15 Pfennig proof with light grey net underprint in vertical upper margin strip of three with black overprint "5 Mk", "20" and Mark 5 Saagebiet", the stamps (postage stamp) are mint never hinged, in the upper margin with fold remnant and horizontally pre-folded above, otherwise in perfect condition, quite scarce in this form, signed Dr Dub