Most record companies did not manufacture Stereo-Pak cartridges themselves; however, the Muntz Electronics Corporation licensed music from all the major record labels and issued hundreds of different tapes in the mid to late 1960s.
Die meisten Plattenfirmen stellten keine Stereo-Pak-Kassetten her; allerdings lizenzierte Muntz Electronics Corporation Titel aller großen Plattenfirmen und brachte zwischen Mitte bis Ende der 1960er Jahre Hunderte verschiedener Kassetten heraus.