Doubling:

If you end up with a winning hand, you can accept the winnings, or you have the option to double it. Should you choose to double, the dealer draws an open card and you can choose between 4 unexposed cards. If you choose a card that is lower than the dealers, you lose you original winning. If the cards are equal, it is a tie, and you have the option to collect your original winnings or double again. If your card is higher, your win amount is doubled. You then have the option to collect your winnings or double even further. You can also choose to Half Double, which means you only double for half of your winning amount.