Those are crafting materials for artifice oand other professions that make crafted gear. You need to pick up the corresponding crew skills to use them ps. you can also sell lots of them on GTN for good money

anyone had any luck looting this off any bosses in taral v Marauder's Foundry Hood? i think maybe the legs dropping is very random

I have run through the Taral V flashpoint many a time trying to get the maruder's foundry head; chest and pant peices, only to get the pant peice so far after about 10 runs. Has anyone else on the republic side been lucky enough to loot the head or chest? because it seems like all you get is that darn sentinal gear Thx for your responses