From Halopedia, the Halo wiki
Based on reverse-engineered stealth pylons utilised by the Covenant, cloaking generators were used by the Banished to hide from the Covenant during their early days. They were later improved by Huragok that were coerced into working for the Banished, and saw more use for preparing ambushes. Cloaking generators generate a cloaking field that conceals infantry, vehicle, and aircraft within its area of effect; during the Battle of Netherop in 2559, Atriox used a cloaking generator to hide the drekar Hammer of Fate and four karves on the surface of one of Netherop's two moons. The cloaking generator shares the same housing as the shield generator.
Halo Wars 2
Cloaking Generators can be built on turret slots of Banished outposts.
Stealth and deception field.
Used by the Banished to hide from wrathful Covenant eyes in their early days, the Cloaking Generator is a reverse-engineered version of the stealth pylons used by the Covenant. When built, the Cloaking Generator disguises the presence of the outpost with a combination of active camouflage and distortion jammers. Even if the Outpost is detected it cannot be directly targeted without the aid of nearby scout units with hyper scanners.
The Banished are never subtle, but they appreciate the power of stealth and ambush. Long years of evading the Covenant's enforcers has made Atriox an adept master of stealth warfare when it serves his needs. Further improvements in Banished multi-modal stealth and jamming technology come from their use of the Engineers, who have been coerced into making modifications that suit the rather blunt ministrations of their Brute operators.
List of appearances