The Colt-Rocker M4A2 is a Paternian carbine, made with much of the same techniques and materials as the M16A5 rifle. During the Japan War, the Paternian Army employed the M16A5 assault rifle, but standard M4A1 carbines. The M16A5 and the extremely extensive use of polymers, as well as polymer-cased ammunition, was very popular and performed well.

However, close-quarters combat and mechanized warfare obviated the use of the M4 Carbine, and a similarly lightened version of the M4A1 was desired. This became the M4A2, and the conversion was swift. By the Japan War, half of all issued assault rifles were the M4A2, the other half being equal parts M16A5 and G3A3 rifles. These rifles were such influential that the RWA developed the ALEK-90, which was derived from the M16A5 among other weapons.

This particular M4A2 is presented as-issue to Paternian infantrymen, featuring an Aimpoint M68 CQO, Dragon Industries MBipod-Foregrip, SureFire M89 flashlight, and Paternian Army Armory M52 Backup Rear Iron Sight