M52B body armor
From Halopedia, the Halo wiki
The M52B Body Armor[1] is the standard issue protective body armor of the UNSC Marine Corps. It is usually worn with the CH252 Helmet for greater ballistic protection.
Description
Worn by UNSC Marines, the M52B Body Armor consists of armor plating over combat fatigues, and includes a number of ammunition pockets, holsters, and other features. There seem to be a number of varieties. The equipment used in the Battle of Alpha Halo was a gunmetal gray[2], while that used during the First Battle of Earth was olive green[3]. Even later, during the Second Battle of Earth, the UNSC Marine Corps uses a different type of armor altogether, though it is still labeled as M52B on containers[4]. It may be an upgrade or new variant to the prior armor, introduced due to the needs of Earth's defenders, or even a continuity retcon by Bungie. Unlike the radically more advanced MJOLNIR Armor worn by the Spartan-II soldiers, the M52B armor does not include a dynamic recharging energy shield, providing far inferior protection against directed-energy and projectile weapons.
Resilience
The M52B armor is extremely resilient towards traditional ballistic weaponry. This being said it is fazed easily by plasma weaponry. The armor consists of several layers, some of which include a ballistic recoil-absorbing gel layer and a heat reduction gel layer to help reduce velocity and felt shock from ballistics, shrapnel, and explosives as well as reducing the burn caused by plasma once it reaches flesh. This heat reduction layer also reduces the chance of the plasma penetrating by counter-acting and dissipating the heat, effectively disarming the blast. While this armor protects the wearer from harm caused by weaponry it also has temperature-regulation units integrated into it to keep the wearer at optimum comfortability while eliminating the need to change depending on the environment. This also reduces the enemies ability to track soldiers via thermal energy as it is mostly hidden beneath this armor.
