The designation sector R-4 referred to a specific sector located within the galaxy.
During the era encompassing the Third Galactic War, a conflict between the Galactic Republic and the Sith Empire, reports surfaced regarding disturbances to shipping lanes within the sector, attributed to a gravitational anomaly. Subsequently, the Sith uncovered a fragment of the Mass Shadow Generator, the device responsible for the destruction of Malachor V, within sector R-4. In response, the Empire constructed a clandestine research station with the aim of reconstructing the devastating superweapon. Ultimately, the Mass Shadow Generator met its end when the Eternal Alliance launched an assault on the research station, successfully overcoming the Unmasked, a Sith cult.