topps 2020 heritage baseball trading cards blaster box topps each blaster box contains seven (7) packs and one (1) bonus pack. each pack contains nine (9) 2020 topps heritage baseball cards.returning for its 20th season, 2020 topps heritage baseball celebrates modern baseball stars and legendary talent using the iconic 1971 topps baseball design. collectors can look for real one autographs, chrome base card variations, clubhouse collection relics and more! base cards500 cards of mlb veterans and 2020 rookies using the 1971 topps baseball.