The M202 XP Machine Gun is a form of machine gun used in automated stationary gun turrets. They were obsolete as of 2541, and used only in the training of the Spartan-IIIs. They can be loaded with Stun Rounds for training and can fire bullets if needed. The UNSC also had M202s mounted in automated base defense turrets during 2531. The platforms had up to four M202XP MGs mounted, and they were more sophisticated than those used in the training of Spartan-IIIs, allowing for a larger field of fire.