Proof POSTAGE DUES: 1931 ½d. to 6d. imperforate proofs in the issued colours on gummed paper, each partially affixed to presentation card (62x103 mm.) with Bradbury Wilkinson & Co. Ltd. label at foot, the ½d. dated "23 Feb 1931" and the 2d. marked "Presented to the Administrator of S.W. Africa Mr Werth", both in pencil on reverse. A very rare set. Photo