This is a pretty good prop to use for this classic trick. If you already know this trick, I wouldn't
go and buy the card because I think there are other great ways to reveal it, but if you don't know
the trick then pick it up. I did this trick for my math students a while ago and liked it. However,
they'll quickly pick up on how it's done, so I find that it's better used as a gag rather than
magic.