Crusted Iron Horde Pauldrons

Crusted Iron Horde Pauldrons is a drop from various Iron Horde corpses that can be turned in with 50 Iron Horde Scraps for a Bind to Account transmog shoulders. Alliance players exchange with in the Dwarven Bunker garrison building. Horde players exchange with in the War Mill garrison building.

Source
This item can be collected from Iron Horde corpses in Warlords of Draenor dungeons.