Souvenir Folders or postcard booklets like this one contained a set of postcards that folded up into a cover. These accordion fold postcard folders were popular in the 1940s and 1950s. Instead of choosing a single postcard, you could send someone a dozen or more cards all folded up into the size of one postcard. The price was the same as a first class stamp.
Lake Charles Souvenir Folder, Lake Charles, LA
Undated 1950s – Published by Elam News Agency No. D-13356 – Divided Back
Made by Curt Teich & Co. Chicago, IL