This came from an old magician’s estate. Maker unknown. No instructions but the working is obvious once you have the slate in your possession. The surfaces of the slate and the wooden framework show some wear from use but the mechanical parts of the slate work very well.
Have two playing cards selected and returned to the deck.
Introduce the blank slate and cover it with a cloth.
When the cloth is removed the two names of the selected cards are found written on both sides of the slate! One card on each side!
Very easy to work.
Self-contained; no flaps used.