It is a three-form transformable fighter called the Armo-Fighter AFC-01 Legioss, which is used by the humans to fight the Inbitaliens that have invaded Earth.
It has 3 modes: Armo-Fighter (Jet/Starfighter), Armo-Soldier (GiantRobot) and Armo-Diver (Gerwalk). The Legioss can be connected in tandem with the Tread heavy mecha (which acts as an aerospace booster).
The Legioss is somewhat similar in design to the VF-1Valkyrie variable fighter from Choujikuu Yousai Macross (1982), which aired a year before Mospeada (1983).
The Legioss was renamed as the VFA-6 Alpha Veritech (also known as the Alpha Fighter) in the third arc of the Robotech adaptation.
