3 - 12 Pfg postal stamps, varieties "with on gum side printing other stamps", all 12 catalogued values respectively paper variants, in horizontal pairs, in perfect condition mint never hinged, in this kind extremely rare, expertized Sturm and photo expertize Kunz BPP (2018) "the complete, mint never hinged sets in horizontal pairs are genuine and in perfect quality. The to come about this varieties is until today undetermined. ", by Michel unpriced