The 2021 Topps Heritage Baseball Exclusive Factory Sealed HANGER Box contains 35 standard-sized baseball cards featuring players like Fernando Tatís Jr., Ronald Acuña Jr., and Mike Trout. This set, manufactured by Topps in the United States, includes cards from the MLB World Series and offers a variety of exclusive features such as rookie cards and 1st Edition inserts. Each box is sealed and comes with a base set of cards from top teams like the New York Yankees, Los Angeles Dodgers, and Los Angeles Angels, making it a coveted collectible for baseball fans and card enthusiasts.