Your chance to critically hit with Throwing Weapons is increased by 1%.
Throwing Specialization is a Troll racial trait that increases chance to critically hit with throwing weapons by 1%.
Past changes
Patch 2.3.0 (13-Nov-2007): Troll: Bow and Thrown Specialization now increases chance to critically hit with those weapons by 1% rather than increasing weapon skill. Was +5 throwing weapon skill.