This is an original 1950's Post Cereal Advertisement featuring Bill Dickey.
It measures about 10x12 inches.
It is made of some type of foamboard. I do not believe this to be a cut out and pasted to the board. The way the creases and folds are, appear to make this 1 piece.
This was likely an in store advertisement. It either was for the window or countertop.
The condition is FAIR. There are several folds and creases. The backside of the board separated a little. It could be matted and framed which would hide many of the imperfections.