• Malleable Steelweave Mantle
• Item Level 226Disenchants into:
  [Abyss Crystal]: 1-2
• Binds when picked up
  
• Leather
• Shoulder
• 443 Armor
• +64 Stamina
  +65 Intellect
  +56 Spirit
• Red Socket
• Socket Bonus: +4 Spirit
• Durability 70 / 70
• Requires Level 80
• Equip: Improves haste rating by 48.
  Equip: Increases spell power by 90.
• 
• Sell Price: 8 41 55

Source

This item can be found inside Cache of Innovation after defeating Mimiron in the 25-man version of Ulduar.

Patch changes

• Patch 3.1.0 (14-Apr-2009): Added. 
  

External links

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