The players' default AC from the game Armored Core VI: Fires of Rubicon, piloted by the player character C4-621. LOADER 4 is a RaD scout AC using all XC-2000 series RaD produced parts and BAWS produced internal combustion generator. Default armaments include energy blade, assault rifle and right side shoulder mounted missile pod. LOADER 4 is easily distinguished by its elongated head unit, the orange glow on its head unit also giving it an one-eyed appearance. LOADER 4 is painted primarily in gunmetal grey and black, with various glowing orange parts around the body.