MA5 series
From Halopedia, the Halo wiki
The MA5[1] is a weapon series used during the Human-Covenant War. The MA5 is a modular weapon system, able to accept a variety of attachments, producing many different variants: the MA5B, the MA5C and the MA5K, all in use with the UNSCDF.
The MA5 series was preceded by the MA3 Assault Rifle, though it is unknown if any other models were in use between the UNSC's dropping of the MA3[2] and its adoption of the MA5.
