- “He's got Power Armor, Chief! Take down his shields before you get close!”
The power armor  is the Jiralhanae armor featured predominantly during the events of the Covenant Civil War. Though in use already by 2524, it saw widespread combat field operations only sometime during the later years of the war. This armor made its appearances in games, Halo 3 and Halo 3: ODST.
Power armor serves as extra protection to the Jiralhanae, who, before the Great Schism, had generally poor armor systems (with a few exceptions, such as the crew of the Rapid Conversion). Unlike Spartans and Sangheili, it is more of a deflection armor (e.g., bullets will "ping" off the armor only with the help of the shields, and unlike MJOLNIR or Elite shielding, the armor does not produce a visible "shimmer" effect when hit with a projectile). It provides protection from all ballistic and plasma weaponry, and even light shrapnel/explosive protection, until failure of the shielding. It also provides light protection from the environment and other elements.
Note that the armor effect of Brute power armor has been altered in Halo 3: ODST; projectile impacts on the armor now produce a split-second full-body shimmer effect (similar to the effect seen when Elite or MJOLNIR shielding is shot), rather than the bullets simply "pinging" off the armor at the point of impact like in Halo 3.
The armor displays the rank of the Brute wearing it, usually through the color or complexity of the armor. The system is similar to that of the other Covenant races, although it seems to follow its own nomenclature.
As with all energy shielding, it is very good at absorbing damage from projectile weaponry. It also seems to solve the problem the Covenant may have had with finding energy shields that would work on Jiralhanae and be reasonably affordable. Brute shielding appears to recharge generally slower than the Elite's version.
It comes in many varieties, some with more strength than others, and some with useful secondary applications (such as the built in Cloaking in Brute Stalker power armor, and the inability to stick grenades or Needler rounds to Brute Chieftain power armor).
It does not give off as much of a glow as Sangheili and Spartan Energy shields when hit, which can be useful for concealing the wearer's position, and since it falls apart once the shields go down, the Flood cannot use it for themselves. However, if the Flood infects a Chieftain whose armor doesn't fall off, it will still become a normal Brute combat form due to programming restrictions.
The most obvious drawback of Brute power amour is that it, unlike a Sangheili combat harness or MJOLNIR armour, can be completely destroyed, leaving the wearer extremely vulnerable.
In Halo 3, Brute Power Armor is generally inferior in strength to the shielding systems of the Sangheili personal energy shield or MJOLNIR Armor, although this is compensated for by the Brute's natural physical resilience even when unarmored. A standard Brute's shielding is almost half as powerful as that of an Elite Minor (collapsing after 7-9 assault rifle hits on Heroic difficulty, compared to 12 assault rifle shots for a Minor Elite's shields), and even the shielding of a Brute Captain or Brute Chieftain are only on par with an Elite Minor's shields (dropping after only 12-14 assault rifle shots or several plasma rifle bolts).
In Halo 3: ODST, it should be noted that although the shields on Brute power armor in ODST take less than half as much damage from projectile weapons as in Halo 3, meaning they are not at all stronger; it still takes the same amount of fire from energy weaponry (including the Covenant Carbine) to bring them down in both ODST and Halo 3.
Additionally, it is easy to see how damaged the armor currently is via the luminosity of the armor's lights and the presence of sparks and smoke, which signifies that the armor's shielding is almost depleted. Finally, the armor is unable to recharge after complete overload (unlike Sangheili and Spartan shielding), and in fact, falls apart completely.
This may be caused by the system being less robust than other shielding systems (but is most likely a gameplay design choice.) However, as long as the system is not overloaded completely, it recharges as rapidly as the other systems do. Still, the Brutes are already naturally resilient, and can withstand substantial amounts of damage even without their armor. However they are very susceptible to headshots once their power armor fails.
It also falls prey to the usual weaknesses of energy shielding, including weakness to plasma weaponry. Of course, overcharged Plasma pistol shots can take it down in one hit pertaining to the difficulty.
- In Halo Wars, the Jiralhanae commanded by the Brute Army Commander all wear power armor.
- Additionally, Brutes will no longer flinch from shots from Sniper Rifles, etc. while the shields are still active.
- In the marketing campaigns for Halo 3 and Halo 3: ODST, the power armor worn by the Brutes does not deflect incoming damage, as Brute infantry are repeatedly struck by incoming fire as though they had no shields. This can be seen in Halo: Landfall and We Are ODST.
- It is possible that the armor never saw extensive action before the Civil War because the Sangheili used their political influence to restrict the military power of the Jiralhanae, similar to the situation with the Rapid Conversion.