Disc tax thro' Car windscreens

A passer-by is invited to consider a tax disc in a car windshield.
A hand is placed on the position of the disc, under the hand of a tax disc is slowly released!
The magician withdrew his hand to show that the tax disc in the windscreen is missing!
At the same time, it gives tax disc to go through to consider.

Methodius.
I heard a couple of theories about how the tax disc is "disappeared", but the most plausible is this.The disc inside of the windshield is fired from his position by an accomplice. The accomplice is placed at the rear of the car and pulls the disc clear through a fine wire.