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Were you looking for the M95 Lance GMWS, the terrestrial missile emplacement?
Aesthetically, the M97 GMWS is near-identical to the M95 missile battery, albeit larger and lacking the large base unit common to both the M95 GMWS and the M71 Anti-Aircraft Gun. It is also functionally similar, holding six high-explosive, self-guided missiles, firing in salvos and using a superficially similar firing turret launcher head; however, unlike the solely terrestrial M95, the M97 GMWS is optimized for operation in both atmospheric and exoatmospheric conditions. It is often installed atop turrets for defensive capability against enemy craft on the exterior hulls of space stations, space elevator terminus platforms and refit stations as well as larger capital ships, being the most popular type of weapon to be utilized in this role.
The UNSC Infinity had several M97 missile batteries mounted on its dorsal surface. After the ship crash landed inside the shield world Requiem in July 2557, John-117 had to reactivate the batteries to help repel Covenant forces. When the Infinity came back to Requiem in 2558, some of the M97 missile batteries were deployed on a select few UNSC bases on Requiem's inner surface, such as Galileo Base.
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