[quote=Foster]
Source: Arms Race

Sol Defense Group 3/A-5.

2 of 8 ships remaining.

Sitution: Critical

Likewise,[url=http://halo.wikia.com/wiki/S4/BRT/1/7] S4 (4th planet from Sol, Mars) 1st Recon Battalion, 7th Marines.[/url] Sans Charlie-company, which was too busy winning the war elsewhere.

[url=http://en.wikipedia.org/wiki/Logistics_Combat_Element]S4/BLCE-1/7 is a Logistics Combat Element[/url] AKA: Pelican-drivers.
[/quote]
I think I did pretty good determining the marine-contingent on Mars. [url=http://en.wikipedia.org/wiki/7th_Engineer_Support_Battalion]And BLCE-1/7 is probably based on this unit[/url]