This Guatemalan airmail stamp, originally issued at 3 centavos, was later privately overprinted to commemorate the nation’s football triumph at the III NORCECA Football Championship. The bold black overprint reads “GUATEMALA CAMPEON / III Norceca Foot-Ball”, celebrating Guatemala’s regional soccer victory. The base design depicts the Instituto Guatemalteco de Seguridad Social building, engraved by F.G.M. and inscribed Correo Aéreo. Such commemorative overprints were produced in limited quantities, making them sought-after by collectors specializing in sports-themed philately and Central American postal history.