Made in America - 12 first day covers with color stamp, USA

A unique series of miniature sheets from the US Postal Service is dedicated to the heroes of work in the early 20th century. The 12 black-and-white postage stamps show fascinating and at the same time dramatic insights into the not always harmless working world of the time, based on historically moving photos. Every first day cover is franked with a stamp from the small sheet and canceled with a colored first day special cancellation.