The effect uses six red backed and six blue backed cards (both sets depicting the six sides of a dice), as well as a plexi-glass holder. As a prediction, the magician puts two blue backed cards face down into the holder. The spectator then rolls an imaginary die two times in a row. The magician then takes the two red backed cards corresponding to the two numbers thought of by the spectator and places them face up into the holder.  When the magician turns the holder over the audience can see that the prediction cards match the chosen cards exactly.  The numbers are different every time and there is no force of any kind.

This trick requires no sleight of hand and can be easily mastered.  Astor has added many nice touches to this effect to add to its deceptiveness.