Black green, perforation C, horizontal raked strips of three from the right upper corner margin with a four-digit red counting number on this 50 Pfg sheet margin. The rare unity is mint with original gum without hinge or trace of a hinge and shows three tiny spots of stain visibly and the margins are yellowed, the right stamp with trace of a fingerprint. Catalog value according to Michel 3.600.-for perfectly mint never hinged. Certificate A. Schlegel BPP (06/2011)