The Playing Cards set was issued by Duke around 1888. These cards can be used as a regular set of playing cards, although they are the regular small tobacco card size (roughly 1 7/16 x 2 3/4 inches). The complete deck is composed of the 52 regular cards plus a joker (53 cards total).
The only two cards that indicate they are not just a small set of cards are the Ace of Spades and the Joker. The Ace of Spades can be found with either a Duke’s Cigarettes or Turkish Crosscut Cigarettes ad. The Joker shows Duke’s Little Joker.