Armbrace?

Hello, what is this Armbrace everyone is talking about and selling and how are they acquired?

All you need to know about it: http://gw.gamewikis.org/wiki/Armbrace
It's the item you need to have in order to get a Tormented weapon of your choice.

It's an Armbrace of Truth. These are traded for Tormented items.

They are also used as a trade commodity, kinda like ectos are.

I would have posted the link, but I always do that, so I figured I'd give some actual info.

It's a token that you can trade for a fancy weapon. You can get one by trading in 15 of each Anguish gemstone (Margonite, Stygian, Torment, Titan) to a Spirit of Truth in Domain of Anguish (the elite area of Nightfall). It's the most expensive stacking item in the game so it is used in ultra high end trading between players where the value of ecto just doesn't cut it.

Thanks guys. I would have looked it up on guildwiki, but I can't access it at work; blocked.