Cover franked with 1922 4c slate and 1922 25c black on emerald GV issue (SG 123 & 133) tied by BELIZE cds's dated 22 MAY 1929. Flown on the Belize - Cristobal, Canal Zone first flight by PAA with oval 'BELIZE MIAMI - PANAMA FIRST FLIGHT' first flight cachet in violet and black on blue airmail label on front. Addressed to CRISTOBAL, CANAL ZONE with arrival cds on reverse. A rare flight, only 60 covers were carried. (Muller #4, rated 1500pts)