The M245 Squad Automatic Weapon is a Paternian belt-fed 5.56mm light machine gun. The weapon was developed in response to the limitations of the M60 machine gun when employed as a light machine gun. While certainly capable of doing so by the nature of its design, it caused logistical issues because of the cartridge; it used a 7.62mm NATO cartridge which was incompatible with the standard-issue 5.56mm NATO caliber M16 rifle.

Thus, the Paternian Armed forces set forth to develop a 5.56mm light machine gun, and settled on two designs; the M18 and the M245. The former was a variant of the M16A1, fitted with a heavier barrel, revised handguard, and a bipod, and the latter is a belt-fed machine gun which can accept M16 magazines. The M18 emphasized greater precision, while the M245 emphasized greater volume of fire.

The Paternian Army and Air Force would settle with the M245, while the Marines would settle with the M18. In practice, both weapons were considered quite effective; Soviet troops in Thailand often found the M245's cyclic rate of 1,000 rounds per minute to be quite unnerving, earning it the nickname the "Paternian Ratchet," after a common instrument used to scare birds. The belt-fed nature and quick-change barrels only added to the fear factor of the weapon. The weapon was quite popular with Paternian troops, who found the overwhelming firepower of the weapon useful against large concentrations of Soviet forces.

It should be noted that the M245 was quite an accurate weapon for its type, although it is still less accurate in both testing and practice over the M18. This particular weapon is fitted with an M121 Machine Gun Optic, developed for the M60, M245, and the M18. However, only the M245 employed it; later models of all three machine guns would employ the Elcan sight as M145.