Jump Jet attachments
From Halopedia, the Halo wiki
The Jump Jet attachments are prototype safety restraints employed on shoulder pauldrons, presumably designed for use by either pilots or jetpack users, and compatible with MJOLNIR Powered Assault Armor/Mark V and GEN3.
The Jump Jet shoulder pauldrons can be unlocked in the Halo: Reach's Armory through the game's purchase system via the use of cR. In Halo: The Master Chief Collection, the Jump Jet shoulder pauldrons are attainable in the Season 1: Noble progression system.
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