From Halopedia, the Halo wiki
Emerson Tactical Systems is a human corporation producing materiel for the United Nations Space Command. It was the developer of the VOID DANCER-class Mjolnir. Because the armor does not meet all Mjolnir standards, Emerson sacrificed Void Dancer's compatibility so the company could integrate its own black-box components. Emerson also manufactured the MK50 Sidekick.
List of appearances