Colorful advertising Poster Stamps began in the US around 1912.This class of "Cinderella" is not well cataloged and many thousands of different ones were created. Poster Stamps became less colorful, and disappeared quickly around 1939, when they were replaced by WW2 patriotic labels. The Studebaker set of 12 is a great example of product advertising. Many poster stamps were issued to promote tourism. The Aurora, IL set, also from the early period, and the New Zealand set, desirable and hard to find is from the 1930's. Events are a major class of poster stamp, and were issued for Royal visits, philatelic exhibitions, worlds fairs, and conventions. Some Poster Stamps were issued for an idea; often political, but not in the case of these created by The American Railway Association to promote "Safety". Educational, including famous people, is another class of Poster Stamp. Aviators were immortalized in this set of 16, used as a gas station premium, and would have come with a paper album to mount them.