This is a one of those effects where you pretend to teach the audience how to do a trick and then end up pulling a fast one on the audience. You show three pip cards and ask a volunteer to pick the center card. Mysteriously the card changes to suit card (say Queen of spades). You explain that the secret behind this trick is the Queen of spades, which was hidden behind the gimmicked flap, which appears to be the center card. You now proceed to do the same trick one more time and this time the Queen of spades turns into a blank card right in front of the unsuspecting audience.
An easy to do trick at a very affordable price.