Containing 3 issues of High Passage (# 3, 4, 5), the Bundle is the creation of Traveller owner Far Future Enterprises. The accompanying document notes that these magazines were “unearthed from the archives of Game Designers’ Workshop” (GDW).
High Passage was a 3rd party digest-sized magazine published (1981-2) by FASA in support of the Traveller roleplaying game.
HP issue and article list over at my RPG reference site.
The document that comes with the High Passage Magazine Bundle is a fun read for those of us into RPG history. The top is a list of articles. The essay at the bottom, titled The Story of High Passage (Jim Cunningham, May Day 2020) is an uplifting tale of gamer friends who got themselves published, worked with the Keith Brothers, and maintained a decades-long friendship with Marc Miller (FFE).