• The Leviathan's Coil
• Item Level 226Disenchants into:
  [Abyss Crystal]: 1-2
• Binds when picked up
• Unique-Equipped
• Finger
• 448 Armor
• +63 Strength
  +94 Stamina
• Requires Level 80
• Equip: Increases defense rating by 32.
  Equip: Increases your dodge rating by 34
• Sell Price: 7 56 23

Source

This item drops from the Flame Leviathan in the 25-man version of Ulduar.

Patch changes

•  Hotfix (2009-06-01): "The Leviathan's Coil ring has had its armor reduced from 882 to 448 to properly reflect the item level."
  
• Patch 3.1.0 (14-Apr-2009): Added. 
  

External links

• Battle.net (EU)
• Wowhead
• Thottbot
• WoWDB