South West Africa 1926 KGV £1 VI Plate No1 Corner Pair UM, Rare

1926 KGV £1 deep green & deep red, Setting VI, 9½mm between, "South West" 16mm long (SG 40/CC 51). PLATE NO1 CORNER CONTROL PAIR, Superb fresh UM from bottom left corner. A most elusive plate piece, few of the possible 80 control pairs ever existing (from only 20 sheets printed, ie only 20 possible each corner) survive. (cvR135000). See additional image.