The Mystery Binder with older baseball cards is a collection of sports trading cards stored in protective sleeves within a binder. This product offers fans and collectors a convenient way to organize and display their baseball card collection. The mystery aspect adds an element of surprise and excitement as you never know what cards are hidden inside the binder. It's a great way to add to your collection or make a unique gift for a sports card enthusiast. I don't really know about baseball but it is filled with older cards from the 90s and earlier.