The M-41 MK 2 Plasma Pulse Rifle is an energy weapon designed and used by the ISA. It possesses both an ion
"stun" mode (which can still be lethal) and plasma "kill" mode. It also has and underslung pump-action concussion grenade launcher. Despite being an energy-based weapon, it has a standard STANAG-looking magazine in a bullpup configuration.
The MK 2 is an obvious reference to the M-41 pulse rifle from the movie Aliens. It shares a similar color scheme and design. Both have an electronic ammo counter, carrying handle with builtin sight, and andunderslung pump-action grenade launcher. However the MK 2 does have several key differences, most notably a bullpup design and plasma ammunition.