The Gundam F90 is a prototype unit developed by the Strategic Naval Research Institute under the "Formula Project", a plan to create small mobile suits. Standing at only 14.8 meters compared to the 18 meters tall RX-78-2 Gundam, the Gundam F90's downsizing was achieved through the use of micro-honeycomb structure obtained from Yashima Heavy Industries, enabling its armor and movable frame to be made lighter. It also has a downsized reactor, but its output is 1.5 times that of existing mobile suits. With a total of 51 attitude control thrusters placed throughout its body, the Gundam F90 is also highly mobile and maneuverable. A total of three Gundam F90 units were built and are known as Unit 1 to Unit 3.
The F90 has 11 hardpoints for mounting the Mission Packs, sets of optional equipment and armaments, to meet specific needs or combat situations. The locations of these hardpoints are: two on top of the shoulder armor, one on the backpack, two on the sides of the forearms, two on the front skirt armor, two on the side skirt armor, and two on the sides of the legs. These hardpoints are covered when not in use.