Jacob Daley's The Itinerant Pasteboards:

Craft edition tuck cases made of premium Cotton Gmund paper from Germany

In addition to that it's the only card with a back of a different color

the methods for these effects are cumbersome and often call for elaborate special props

Then show the cup empty

Modern Flap Card (Bildseite zu roter Rückseite) | Hondo Hondo Jacob Daley's The Itinerant Pasteboards:The Flap Card was first introduced in 1922, in Professor R. Kunard's Book of Card Tricks . In the decades since, it has become a staple in the routines of magicians worldwide, used to produce all sorts of stunning effects. However, limitations of the original 1922 design constrain these performances: magicians must precisely position their audience, keep constant pressure on the card surface, and perform tricks almost immediately after setup for best