This is a super version of the classic 'Age Cards' magic trick. Here, instead of calculating someone's age, you'll know a random playing card that they're simply thinking of. What's more, you don't even have to do any calculating, the 'Telepathy Cards' do it for you.
The effect is, any card is simply thought of by a spectator, the magician then places eight transparent cards onto the table (each card is printed with a variety of miniature cards on them). The spectator simply picks up the cards that have the chosen card printed on them, the performer simply gathers the remainder and instantly names the thought of card.
Note, this is a pocket size version of the Computer Card magic trick, this set is the same size as regular poker playing cards. The video demonstration shows the trick using the larger Computer Card set.