A card is selected by a person. A bet is made that your card is 1/2 of his. The spectator has a 5 of Clubs, so he takes that bet only to discover that the magician flips over the 2 1/2 of Clubs.
Easy to do!
5 great specialty printed Bicycle cards, printed by USPS. The four twos are two and a half cards and there is one “half” card include. This card is the Ace of Spades cut in half via printing.