MJOLNIR Powered Assault Armor/M variant
 Development and history
The MJOLNIR/M variant was first manufactured in the Misriah Armory facility on Mars in 2528, three years after the Mark IV was released in November 2525. Like most MJOLNIR variants, the later model of the Security helmet has been upgraded to be compatible with all current generation MJOLNIR Mark VI variants. The M variant helmet, or a helmet greatly resembling it, is also worn by non-SPARTAN security personnel, such as those assigned to the SPARTAN-IIs' training facilities.
 Mark V
 Helmet characteristics
Base price: 250,000 cR, General
UA/HUL price: 200,000 cR, General
CRBN/CNM price: 200,000 cR, Legend
Two upgrades are available for the helmet, the first adds an Up-Armor plate with a Hardened Uplink Module on the right side (UA/HUL), and the second adds a Chemical, Biological, Radiological, and Nuclear Module with a Command Network Module on the left side (CBRN/CNM). The CBRN attachment does not take on its usual gas mask appearance, instead it is the same as the CBRN that is standard on the EOD helmet.
 Shoulder characteristics
Unlock: 70,000 cR for left shoulder; 275,000 cR for right shoulder, rank of General needed for both.
The right shoulder is equipped with a Kukri.
 Mark VI
 Helmet characteristics
Unlock: Get a total of approximately 1000 gamerscore in Halo 3.
The helmet's most noticeable feature is the larger, more prominent "figure-eight" shaped visor which looks almost bug-eyed. It bears resemblance to that of a modern day fighter jet pilot helmet. This helmet is inspired by the protagonist of Marathon, although the mouth is covered. The helmet is large with a small raised section on the forehead in the form of the Marathon logo. Wearing the helmet will also add a small antenna and dial to the right shoulder.
The prominent bug-eyed shape has been toned up, and the helmet looks bigger overall.
 Shoulder pauldron characteristics
Unlock: Officially, the Security shoulders unlock when the player has attained at least 750 Gamerscore points from Halo 3. However, the shoulders are renowned and well-known bugged items.
The shoulder pieces are quite largely rounded, with a section with an upper center, trapezium-shaped arm guard going out the bottom and a rounded section above that. It should be noted that this shoulder permutation is prone to a glitch that may cause you to not unlock them until you have 1000 gamerscore; however, another glitch has occurred that unlocks the Security shoulders before reaching 750 gamerscore points in Halo 3.
The shoulders are less rounded than the Mark V.
 Chest characteristics
The Security Armor does not have a chest plate, although wearing the helmet will give the player a distinct "antenna and dial" on the right side of the back plate. This may be a reference to the antenna Master Chief had in the pre-Halo: Combat Evolved at the Mac World Trailer. The fact that the Security armor predates the standard Mark V armor may support this. Although there is no Security chest piece, the Katana variant chest armor was used mostly with Security and Hayabusa helmet before the Recon armor was given to the public through the Vidmaster Challenges achievements.
- The Halo Encyclopedia erroneously states that the Security armor was manufactured in 2543, as it was manufactured in 2528.
- The MJOLNIR/M variant is based on that of the protagonist of the Marathon series, who is known only as the "Security Officer". The helmet in particular looks almost identical to the helmet worn by Marathon's protagonist. The Marathon symbol is on the helmet just above the visor.
- Unlike in Halo 3, the Security helmet does not feature the Marathon symbol in Halo: Reach. This is likely due to intellectual property concerns, as the symbol is also absent from the rest of the game.
 List of appearances