OBSOLETE PART II

The "real robot" anime is set on Earth in an alternate timeline with 2.55-meter-tall (about 8.4-foot-tall) neurally operated mecha known as Exoframes (Enhanced Xenobiological Organic FRAMEs). The Exoframe technology originated from aliens who made contact with humanity in 2014, and asked to trade one ton of limestone in exchange for one Exoframe. Cheaper than aircraft, tanks, or firearms, and usable by anyone, Exoframe usage easily spread throughout the world.
Source: Anime News Network

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