UA attachments

UA, short for up-armor, is a series of supplemental armor attachments and accessories compatible with the MJOLNIR Powered Assault Armor. Like some other MJOLNIR variants, many of the UA pieces are not exclusive to the MJOLNIR system, but are in use by regular UNSC Army or Marine troops as well.

Halo 3 MCC
The UA attachment is built into the ODST armor/HVY armor, unlockable in armor customization in the Season 6: Raven progression system.

Halo: Reach
All UA variants of armor types can be unlocked in the Halo: Reach's Armory through the game's purchase system via the use of cR. In Halo: The Master Chief Collection, the UA variants of armor types are attainable in the Season 1: Noble progression system.

Helmets
Most of the helmet variants available in Halo: Reach have an up-armored upgrade, sometimes coupled with other external helmet additions, such as the UA/HUL attachment to the Mark V [B] helmet. UA helmet attachments consist of reinforced metal plates or bracers attached to the helmet's forehead to give better protection to the wearer in combat.

Halo 5: Guardians
The UA variant of the Grenadier helmet, the Collar/Grenadier [UA] chest piece, and the UA/Bracer wrist attachments are built into the INDOMITABLE-class Mjolnir, unlockable in armor customization through the Requisition system.

Halo Infinite
The UA variants of helmets and armor types return in Halo Infinite, unlockable in armor customization.

Trivia

 * The UA/Multi-Threat appeared in the Beta as the ASSAULT/SCOUT, this version did not include a belt. Likewise the UA/Base Security [W] appeared as the MP/BASE SECURITY which also did not include a belt. The belt-less versions remained in the files of Halo: Reach, but went unused.
 * It was not until the release of Season 1: Noble in Halo: The Master Chief Collection that the belt-less versions returned.
 * The UA/BUCKLER is named after a small hand-held shield from the middle ages of the same name.
 * The UA/CHOBHAM is named after the composite tank armor of the same name.

List of Appearances

 * Halo 3
 * Remember Reach
 * Deliver Hope
 * Halo Reach
 * Halo 5: Guardians
 * Halo Infinite