Drakuru "Lock Opener"

Drakuru "Lock Opener"s are used to unlock Drakuru Shackles in Zul'drak.

Source
This item drops from the following scourge trolls in Zul'drak:
 * Drakuru Berserker
 * Drakuru Blood Drinker
 * Drakuru Prophet

As a quest objective

 * Trolls Is Gone Crazy!