Dreadnaught Breastplate

The Dreadnaught Breastplate is the Tier 3 plate chest armor for warriors and gives bonuses to strength, stamina, dodge, and overall defense. It is available through quest items in Naxxramas.

Source
The Dreadnaught Breastplate is a quest reward from the quest Dreadnaught Breastplate (quest) which starts with Korfax in Light's Hope Chapel in Eastern Plaguelands. To complete the quest, you must turn the following items to Korfax:
 * 1 Desecrated Breastplate
 * 25 Wartorn Plate Scrap
 * 4 Arcanite Bar
 * 2 Nexus Crystal