I THINK THIS "GIMMICK" IS PERECT TO ADD AN INVISIBLE DECK ROUTINE.
YOU CAN ALSO USE WITHOUT DECK
BUT I DON'T THINK IS ENOUGH STRONG ALONE.
THE ROUTINE HAVE A SECOND REVELATION IN WICH YOU CAN
INVOLVE A SECOND PERSON.
IT'S AVERY GOOD TRICK.
PERSONALLY I HAVE CONSTRUCT A SMALLER COPY
THAT FIT IN MY WALLET.