MA5K carbine

From Halopedia, the Halo wiki

The MA5K Assault Rifle was a cut down version of the MA5B Assault Rifle. It featured stripped down features that appeared almost skelital. The Rifle resembels the BR55 Battle Rifle and could be the weapon that it was based off of. MA5Ks were not as often used for frontline duty, but they came into use by the Spartan-IIIs from 2531 to 2552[1]

Two MA5K Assault Rifles and a MA5B Assault Rifle being held by three Spartans

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