The Federation's successor to the versatile but terribly underperforming GMmobile suit series. Tougher armor and much more power ensured the Jegan was a much greater machine than the countlessly refitted GMs it was replacing.
The RGM-89D Jegan D Type is a minor update of the type, with more flexible loadouts and minute improved sensors and thruster packs. That not much was changed showed a degree of refinement in the original design that enabled it to remain at the cutting edge of mass produced MS even at the rapidly evolving environment of the Universal Century.
