Likely created by a Gem duplicator which was sold out of St. Louis. A crappy little machine no larger than a hankie box. It was marketed as a way of "making your own postcards" in the 1940s, I believe. These could have been run off on a competing product. It isn't too hard to find the mechanical duplicator in a box on the web, but actual prints are less common. These are good examples of cheap home technology meeting the gals and gams of post-war folly. They have a nice "etching" like shading.
Group of home duplicator pinup girls on paper Collection Jim Linderman
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