The Exosuit is a weaponized version of the Caterpillar P-5000 Work Loader designed for heavy combat use. Used by both the United States Colonial Marine Corps and private military contractors like the Iron Bears, the ExoSuit is a "micro-scale" heavy armor solution, bringing offensive and defensive benefits of larger combat vehicles to any individual soldier in battle. It is designed for heavy assault in any difficult environments by combining the staggering firepower with a range of integrated protective systems in the field.
By default, the exosuit comes equipped with an M103 Torrent cannon attached to each arm. These weapons are linked and work together to saturate a broad firing arc with projectiles. When a torrent cannon attacks, it initially fires at a moderate rate and covers a small arc, but "spins up" until it absolutely blankets a large arc with its firepower. Those enemies not amply protected often lose their full freedom of movement as they struggle to survive the onslaught.
The ExoSuit's upgrade replaces the mechanical torrent cannon with an electronically triggered projectile array known affectionately as the "bullet box" - a grid of railguns that come pre-filled with rounds. These railguns can fire simultaneously, and with sufficient frequency to launch multiple projectiles before their predecessors have even left the barrel. The result is a weapon that fires nearly 1,000 rounds a second (rps), a volume of ordinance sufficient to liquefy most targets within seconds.
However, certain exosuits are known to use customized weaponry and systems. One exosuit, nicknamed 'Alice' by Marines, is outfitted with a laser cannon and heavy flamethrower in one weapon arm; there are twin-linked miniguns and a heavy rocket launcher on the other. 'Alice' has also shown far more speed and agility than the lumbering motions of standard Exosuits, being able to sprint rapidly and jump much higher than the average human, though jumping uses extra power that recharges quickly over time.
The Exosuit protects its operator with a suit of integrated systems. First, it has compound multi-layered armor that enables it to deflect lighter projectiles outright. Second, its integrated anti-NBC (nuclear, biological, and chemical) systems permanently protect its wearer from a range of Alien afflictions, including spores, cysts, virulence, acid scarring from Alien blood, and facehugging. Lastly, the system is largely impervious to radiation and fire.
The Exosuit's fire rate enables it to suppress and shred large numbers of enemies, making it particularly useful against melee attackers, since they have a hard time closing inside the weapon's attack cone. While it does not fire armor-piercing rounds, the Exosuit's fire rate is so great that even heavily armored targets can succumb to it, given enough time. Finally, the suit's compound protective systems make it ideal against attackers that otherwise cause side effects on organic troops.
The Exosuit's biggest weaknesses are its limited speed and maneuverability, byproducts of its heavy protective systems. Also, while the exosuit's rate of fire makes the issue less significant than it might be, the suit's bullet's have neither great penetrating power nor long range. A number of enemies are specialized for attacking heavier opponents and can exploit these weaknesses. Also, the Exosuit's designers have yet to integrate the ape suit's recent advances towards full acid resistance.