Destroyer Shoulderblades

The Destroyer Shoulderblades are the Tier 5 Warrior DPS shoulderguards. They provide a bonus to strength, stamina, and critical strike rating. It is part of the Destroyer Battlegear set.

Source
This item is sold by in the Seer's Library on the Scryer's Tier and by  in the Shrine of Unending Light on Aldor Rise in Shattrath City. The cost of the item is a Pauldrons of the Vanquished Defender token.