SOUTH WEST AFRICA 1943 SG130c,var Used

1943-44 War Effort 1s brown (reduced size), type 31 opt, block of 4, ERROR OPT INVERTED, additionally showing the variety 'Smoking L' on lower right stamp (R8/2), centrally cancelled by 'WINDHOEKCOUNTER' cds, dated '17 X 44'. Folded central perfs, but likely to be a unique multiple with this combination of error and constant variety (occurring once in each sheet of 120 pairs !). A remarkable item. - P06709303