The RGM-79Q GM Quel is a mass-produced general purpose mobile suit used by the Earth Federation's elite Titans special unit. It first appeared in the OVA Mobile Suit Gundam 0083: Stardust Memory and was later featured in Advance of Zeta: The Flag of Titans and Mobile Suit Zeta Gundam: A New Translation.

The RGM-79Q GM Quel is the first mass-produced mobile suit created by the Titans special forces, used during the organization's early stages mainly for peacekeeping, riot control and suppression purposes inside space colonies. It can be said that a clear line could be drawn, performance wise, between the more advanced GM Quel and the other mass-produced service models used within the common ranks of the EFSF, signifying the elite status of the Titans unit.

Manufactured on Luna II, the GM Quel was developed using the EFSF's own technology and capabilities as a demonstration of the early Titans' commitment to their "Terra firma" policies, despite gaining the expertise and support from numerous military and civilian contractors, such as the Zeonic Company and Anaheim Electronics after the war. Using the Augusta base's high-performing RGM-79N GM Custom model as the basis of their new design, the Titans redeveloped the GM Custom, simplifying it to make the unit lighter and less complex for the ease of mass production, while keeping its high performance standards relatively unaffected. Any loss of durability and/or reliability as a result of the simplification process was made up by introducing new, innovative design concepts and technology into the machine. One such example is the design of the GM Quel's new arm unit, which would later further evolve into the Movable Frame concept utilized by the RX-178 Gundam Mk-II and the next generation of Variable (transformable) Mobile Suits (VMS).

While essentially just an updated version of the GM Custom, the GM Quel however does feature various minor improvements over its predecessor. The shape of its forehead, chest and shoulder armor has been streamlined, and high performance multi-purpose sensor units have been installed on the lower calf area of both legs and on the slope above the left chest intake. The performance of the existing sensor and communications equipment on the head unit has also been improved. These electronic upgrades allow the GM Quel to better monitor its surrounding environments and civilian populations while on peacekeeping duties. And due to the increased funding and resources enjoyed by the Titans, the GM Quel has also gained the option of being armed with Beam weaponry, significantly improving its firepower. However some colonial garrison units have opted to retain their standard issue GM Rifles instead, so as to minimize and/or avoid causing collateral damage to colony walls.

A specialized equipment testing and evaluation team, known as "Titans Test Team" or "T3 Unit", uses the GM Quel as the basis for their development of the next generation RX-121 series Gundam-type MS. Performance testing of these prototypes are carried out in actual combat scenarios, much like the venerable RX-78 Gundam Series, against Zeon remnants.

By the beginning of the Gryps Conflict in U.C. 0087, the GM Quel, along with other GM series mobile suits such as the RMS-179 GM II, was considered to be out-dated, and was gradually replaced as a frontline unit by the EFSF and the Titans with newer mobile suits such as the RMS-106 Hizack and the RMS-108 Marasai.

Temporary Titans units made up of ordinary Earth Federation Forces use GM Quel painted in red and white Federation colors.