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Helmet Attachments

Helmet attachments are a collection of armor permutation in Halo: Reach. Some of them are compatible with each other while others are exclusive to certain helmets.

UA Attachment

The UA helmet attachment consists of reinforced metal plates or bracers attached to the helmet's forehead to give better protection to the wearer in combat. For more information on other UA attachments, see MJOLNIR Powered Assault Armor/UA.

CNM

A Military Police helmet equipped with the CNM and HU/RS upgrades.

The External Command Network Module or CNM, is an external helmet attachment utilized by the United Nations Space Command.[1]

Two different models are known, one designed for the Military Police helmet, and an Up-Armored variant for the ODST Helmet. The former is standard issue to Special Force unit commanders and Beta-5 Security units patrolling the Inner Colonies, while the latter seems to be exclusively used by the ODSTs. The two devices differ in appearance as well as their pricing.[1]

The CNM is available as a helmet accessory in Halo: Reach. The device for the MP variant is priced at 5,000 cR, while the ODST variant is priced at 1,000 cR.[1][2]

During the Halo: Reach Multiplayer Beta, the Mark V[B] helmet had a CNM upgrade available. The device cost 2,000 cR, but was cut from the final game.

CBRN

HUL

A Mark V/CQC helmet with the HUL device and UA attachment.

The External Hardened Uplink or "HUL", is a device compatible with helmet variants of the MJOLNIR Powered Assault Armor. It is designed for acquisition of military intel, and is required for sensitive operations. The cost of one HUL unit is 5,000 credits.[3]

Sources