Shoulders of the Forlorn Conqueror

Shoulders of the Forlorn Conqueror is a tier 11 armor token. It can be exchanged at in Stormwind City or  in Orgrimmar for the following items:
 * Mercurial Mantle
 * Mercurial Shoulderwraps
 * Reinforced Sapphirium Mantle
 * Reinforced Sapphirium Pauldrons
 * Reinforced Sapphirium Shoulderguards
 * Shadowflame Mantle

Source
This item drops from Cho'gall in the Bastion of Twilight on Heroic mode.

It can also be purchased from the following vendors for :
 * in Stormwind City
 * in Orgrimmar