approximately 221 covers in three binders ranging from C1 through C53, begins with a few early flight covers including October 18, 1918 Atlantic-Pacific flight "Specimen" cover, December 29, 1925 Cristobal to Costa Rica flight, December 27, 1927 first commercial flight Balboa to Costa Rica, and August 3, 1937 Cristobal crash cover, for the regular Canal Zone airmail issues includes a mixture of commemorative flight covers, first days, and commercial/philatelic uses, better including C14 on cover (2), C20 first day cover, and much more, generally fine to very fine, an extraordinary collection which would take considerable effort to duplicate, obviously assembled over the course of decades and ideal for the specialist