From Halopedia, the Halo wiki
The Delta-6 Division is a classified military division of the Office of Naval Intelligence Section Three, composed of highly trained forward deployed operators. Delta-6 fields a small number of Spartan-IVs, as well as unaugmented operators. The division deployed Spartan operators to eliminate key rebel leaders on Talitsa.
Several MJOLNIR [GEN2] variants are used prominently by D6's Spartan operatives. Spartans deployed in lone-wolf operations favor the Ranger variant. The Talitsa mission saw the most prominent use of the Wetwork variant. Hunter-trackers are commonly issued the Stalker variant. Offshoots of the MJOLNIR Air Assault variant have also been considered for adoption by unaugmented Delta-Six operators, but larger-scale adoption of the system has been hindered by its high cost, with each suit costing as much as a dropship. Delta-6 Division operatives are one of the few groups within the UNSC that are trained to use jetpacks in an atmosphere.
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