The 1975 Topps Marvel Comic Book Heroes White Back Sub-Mariner trading card is a highly sought-after collectible featuring the character Sub-Mariner from the Marvel universe. This single-parallel card, part of the base set from 1975, is an original Topps production with a White Back variety. It is a valuable addition to any non-sport trading card collection, especially for fans of Marvel comics and collectors of vintage cards. The card captures a piece of comic book history from the 1975 season, making it a must-have for enthusiasts of the genre.