This is a stimulating gambling trick. 

Six envelopes (marked with numbers)and one dice are shown on the table.

Only one envelope contains money in it. 

One audience is invited to roll the dice.

Open one envelope after getting a number with rolling dice.

If the audience is lucky, he has a chance to get the money.

It sounds very fair to play such a game. 

But even though the audience rolls the dice thousands of times, he won't get the money.

The prop comes with one normal dice and one special dice.

Demo: