BECHUANALAND 1913 1s bistre Specimen, SG82sBechuanaland 1913 24 1s bistre, watermark Simple Cypher, overprinted 'SPECIMEN' (type GB23), left marginal block of 4, SG82s. A very fine and fresh, unmounted mint block of four with full original gum. A unique multiple, not previously available on the market in this form. Provenance: Ex British Postal Museum Archives. Although distributed by the Universal Postal Union (UPU) with the same 'SPECIMEN' overprint, no blocks could exist from that source.