Browse full ranges of MLB World Series Championship Rings and Order your customized rings. The World Series is the annual championship series of Major League Baseball (MLB) and concludes the MLB postseason. First played in 1903, the World Series championship is a best-of-seven playoff and is a contest between the champions of baseball's National League (NL) and American League (AL). The teams who win the World Series Champions, that every team members will get a World Series Championship ring with his name on it. You can Customize yours now with your own player names and jersey numbers.