1931 FLIGHTS OF KINGSFORD-SMITH 3d RED AND 3d BLUE OVERPRINTED O.S. FOR OFFICIAL USE.
EXTREMELY RARE WITH ONLY 28000 PAIRS ISSUED BY THE POST OFFICE MOST OF WHICH WERE CANCELLED TO ORDER .
STANLEY GIBBONS SG O123-O124 PRICED AT £360.00 OR $720.00.
THIS BUDGET PAIR IS EXTREMELY CHEAP.