From Halopedia, the Halo wiki
RECRUIT-class Mjolnir is a variant of the MJOLNIR Powered Assault Armor (GEN2) manufactured by Hannibal Weapon Systems and Materials Group. It is the standard armor for all newly recruited SPARTAN-IV personnel.
The reactor is covered by a "Class-A hardened reactor case". The shoulders are called "Common solid-plate pauldrons". There is a power conduit on the cuisse. The feet have segmented plates to increase mobility. The armor is designed to cope with the strain and duress experienced by newly augmented Spartan-IV.
The standard color scheme for Recruit-equipped Spartans aboard UNSC Infinity consists of orange-yellow stripes at various points, most notably along the center of the helmet, though the suit remains largely unpainted.[Note 1] Whether this color scheme is common among all recently inducted SPARTAN-IVs is unknown.
The majority of the Recruit variants were manufactured by Hannibal Weapon Systems and tested at WG/Facility 93-00/Kotka. Both the forearms and greaves were manufactured by the Materials Group, with the forearms tested at FFG-045's combat lab, and the greaves manufactured on Chi Ceti IV. Testing for the GEN2 version was swiftly done, as by January 2553 a copy of the armor was onboard the UNSC Infinity.
Decades of combat experience with Mjolnir suits informed the design and electronics hardware architecture of the RECRUIT helmet.
Newly inducted Spartans are required to use the Recruit-class armor for an individually determined time frame before requisitioning custom kits. The armor's performance consistency raises eyebrows among the more experienced Spartans, however, and despite its popularity, many Spartan-IVs opt to diversify the armor with other variants.
Available skins: Prime (PRME) and Tiger (TIGR)
Halo 5: Guardians Multiplayer Beta
In the Halo 5: Guardians Multiplayer Beta there was a "BRN" skin which became the "Charred" skin in the final game. This skin had descriptions for it as follows:
Halo 5: Guardians
Available skins: Charred, Marked, and Proven
In Halo 5: Guardians due to the "Body" having a predefined customisation this armor set permanently has the following parts from Halo 4:
Halo 4 skins
Halo 5: Guardians skins
List of appearances