Scotch & Soda by Johnson Products
Item Number: JO1443
A Half Dollar and a 20 Centavo are given to a spectator to hold behind his back. Magician asks for the half dollar which the spectator successfully hands over. Next you ask for the 20 Centavo. He can't hand it over because it's changed into a quarter.
Add the Scotch & Soda book. Contains 55 tricks you can do with a Scotch & Soda.