Tattered Hexcloth Sack

The Tattered Hexcloth Sack is a 20-slot container which used to be obtained through completing a series of quests dealing with the old Zul'Aman raid.

Source
This item is no longer available in the game. The quest was updated in Cataclysm and now gives Tattered Hexcloth Bag in its place. For people who have completed the quest and received this bag already have the option to do the new quest for the Zul'Aman dungeon to receive an additional bag.