 It was replaced by the PowerBook 180 in 1992.Though the PowerBook 100 is the direct descendant of the Macintosh Portable based on its internal architecture, the 170 is the Portable's direct successor.A no-compromise, portable version of the desktop Macintosh, the 170 includes virtually all of the features incorporated in the original Portable, as on a comparable desktop of the day, but in a smaller and sleeker case design.