1928, carmine surcharges (45 degree angle) ''Ecuador. Provisional'' on Air Post stamps of Colombia 50c/10c-3s/60c and Air Post Registration stamps with surcharge 1s over red ''R'' on 20c gray, complete set of six, nicely centered, full OG, previously hinged, VF, C.v. $685, Est. $250-$300 (Image)

POSTAL HISTORY GROUP: 1928-30, five flown covers, including First SCADTA Flight Guayaquil - Barranquilla, and semi- official air post set of 10, two covers have SCADTA labels added (look dubious), some conveyance flaws, set with full OG, hinged, all F/VF, Est. $150-$200 (Image)