This lot features (4) 2009 Upper Deck Baseball #4 Ken Griffey Jr. rookie 20th Anniversary pop culture 1/1 Printing Plate cards. All four cards are the only ones in existence. Printing plates are often inserted as 1/1s in packs after being used to print the cards. All four of these printing plates were used to create the 2009 Upper Deck #4 Ken Griffey Jr. card.