German Democratic Republic. State Bank of the German Democratic Republic. 1971-1975 Issues. Date: 01.06.1973. Dimensions: 138 x 58 mm. Watermark: Friedrich Engels. Material: Paper. Solid security thread. Printer: VEB Wertpapierdruckerei, Leipzig. Multicolored front and back printing, predominantly red. Description of the front: Background made up of guilloche patterns. Texts in German. Portrait of the father of communist theory, the German philosopher and author Friedrich Engels (1820-1895). Letter and numbering with 7-digits in red. Value "FÜNFZIG MARK" in a rosette in the center. Coat of arms of Germany. No signature. Description of the back: Texts in German. Coat of arms of Germany. Background composed of guilloche patterns. Value in letters "FÜNFZIG MARK". Above, view of an oil refinery. Replacement note with Z prefix.