1920, First Air Post issue, six proofs of Airplane surcharges on blank pieces, black and red of 14k on white paper, black of 24k on cream paper, two black and one green of 28k, two on white and one on cream paper, no gum as issued, VF and rare, two with experts' hs on reverse, Est. $250-$300

250.00

1922, Second Air Post issue, six proofs of Airplane surcharges on blank pieces, three in black of 50(h) on creamy thin card, on creamy paper and on creamy piece from an old poster; one in black of 100(h) on creamy thin card (small spot of paper scratch on reverse); two of 250 (h) in black or blue on thin cards, no gum as issued, mostly VF and scarce, four with experts' sign on reverse, Est. $250-$300

250.00