The 2023 Leaf Trinity Baseball Mega Box contains a total of 10 cards per box, with 7 base cards, 1 memorabilia card, and 2 steel cards. The set features cards from Major League Baseball, with a focus on the MLB World Series. Each card is in standard size and is part of the 2023 Leaf Trinity collection. This exclusive set includes serial numbered cards, rookie cards, and inserts, making it a sought-after item for baseball card collectors in the United States.