The Democratic Underground Forum has a thread about tactical corsets for DU ladies with some insightful comments from jmowreader:
In the old days, soldiers mounted their canteen cases, ammo pouches and so on to Load Bearing Equipment, otherwise known as web gear. There was a pistol belt, a pair of suspenders and then all the weird crap we hung off the system--rifle cleaning kits and of course the most important part of the whole system--the Tabasco pouch! (This is no shit: The McIlhenny family, who makes Tabasco, has long supported the military. Once upon a time, if you sent them a letter with a return address on a military base telling them how much you liked Tabasco, they'd send you a free bottle of it and a pouch, which was made by the Bianchi holster company so it was a high quality product, to hang your Tabasco off your LBE. A lot of us got them. I don't think anyone ever attached it to LBE, though; we were always afraid of losing it, it was so cool.)
In the Modern Action Army, LBE has been replaced by the Modular Lightweight Load-bearing Equipment system, or MOLLE. Instead of the web belt and suspenders, they give you a vest...which, unfortunately, barely conforms to your shape if you're a male. Female soldiers who are C cup or larger don't fit into the issue vest; I sent a few females back to Central Issue Facility to exchange MOLLE for regular LBE because MOLLE just would not fit them. (CIF was normally pretty good about this--they would look at the troop, decide the MOLLE vest wouldn't fit and issue the traditional LBE. Sometimes one slipped through. In the 21st century, though, MOLLE is all there is.) MOLLE comes in several sizes; walking around in an Extra Large vest that hangs down below your ass when the vest is SUPPOSED to stop right at your waist because your chest won't fit in one the right length is no solution. A "tactical corset"--MOLLE made to fit a female soldier--would be a gift from the gods to even moderately-endowed soldiers.
Now understand: the "tactical corsets" they're displaying are made of leather and they've got some goofy accessories, because leather MOLLE and fun stuff like the tactical lipstick case gets people talking about their product. I think they know if this shit's going to sell it's going to be made out of Cordura like issue MOLLE is. (Then again...I don't know if the tactical "lipstick case" is really all that goofy--the issue camouflage stick would fit in it, and everyone wears camo when they go downrange.)
You're right on the money, as the final Tactical Corsets are indeed 1000 Denier Cordura ballistic nylon and the lipstick case is indeed versatile for everything from camoflage to batteries to chapstick to single rounds of special purpose ammo.