S4/BAG/2/5
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Template:Ratings Template:Infobox Military Unit
S4/BAG/2/5 was a UNSC Marine Corps unit. It was stationed on Earth in 2552. That year, they were assigned to Sol Defense Group 3/A-5 when the group requested rearmament.[1]
Speculation
It is possible the S stands for the company, Sierra. The 4 may be fourth platoon of S Co, or fourth battalion that the company is part of. BAG could stand for Brigade Assault Group, which would be the infantry element of a reinforced Marine regiment, or Marine expeditionary brigade. The 2/5 could either be 2nd Battalion, 5th Marine Regiment, or 2nd Regiment, 5th Division. This is simply conjecture and should not be taken as official.
Halo: Evolutions suggests that the first part of the designation refers to the planet the unit is garrisoned on. It gives the example as "E2/BAG/1/7", where "E2" stands for the colony world of Eridanus II.[2] Based on this piece of information, it would appear that "S4" stands for Sol IV - Mars. Continuing with this, the "2/5" may mean "2nd Battalion, 5th Marine Regiment", as what was previously suggested as a possibility above.
