PUAS = Postal Union of the Americas and Spain - Argentina, Bolivia, Brazil, Canada, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, El Salvador, Spain (including the Balearic Islands, Canary Islands, Alhucemas Islands, Ceuta, Chaferinas or Zafarani Islands, Mellila, Penon de Velez de la Gomera, Tangier, and Andorra via Spain), Uruguay and Venezuela. The US usually had special treaties in force with Canada and Mexico.