I found these on eBay and, honestly, I have no idea exactly how they might be used. The material is some sort of card board. Here is what the front (proper text orientation) looks like:
And the underside looks like this:
That’s not a blurry picture, that’s what the underside looks like. My guess is that these are proofs for advertising print plates for newspaper ads. If anyone has any more information on exactly what these are or how they were used, please contact us.
If you look at the cookware pieces, you will notice that they are the pre-1968 era styles.