The 1990 Donruss Baseball The Rookies Factory Set #1-56 is a vintage collection of baseball trading cards featuring rookie players from the Major League (MLB). Manufactured by Donruss in the United States, these standard-sized cards are made of card stock and are part of the original 1990 set. With 56 cards in total, this baseball set includes iconic players and is a sought-after item for collectors looking to add a piece of baseball history to their collection.