Mobile suits are the most popular and most numerous type of mobile weapon. They are humanoid combat vehicles, typically employing two arms to deploy weapons, two legs for propulsion, and a head that acts as a main camera and sometimes houses a secondary weapon that acts as a rotating turret (with the head itself providing the rotation). Typically speaking, a mobile suit is approximately 60 feet in height, with a cockpit located in the unit's torso. However, exceptions are not uncommon; units that are much larger or slightly smaller are not unheard of, and occasionally the cockpit is located in the head or (in semi-rare cases) the crotch, as well. The name "mobile suit" is believed to be a combination of the terms "Mobile Infantry" and "powered armor suit" from the Robert A. Heinlein book Starship Troopers. Different terms exist to differentiate mobile suits from ordinary space suits used to protect individuals in vacuum; for example, Universal Century makes reference to "normal suits" or "pilot suits", while After Colony uses the term "astrosuit".
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