Colourpicture Publishers published this unusual style of Plastichrome Private Message Card, circa early 1960s. This style seems like a clever idea, but it never became popular. The postcard has a gummed edge and is scored so the message area can be covered and the card sealed before mailing. The gummed strip on the side is perforated so that the recipient can tear the card open to “look inside.”
The overall size of this card is 8-1/4″ X 4″. The portion to the left of the fold line is about the size of a regular postcard. This style of Private Message Card was also used for view cards. The view cards that I have seen have two different images–a larger one on the left and a smaller one to the right of the fold line.