Conjured Glacier Water

Conjured Glacier Water is created by mages and helps restore mana to a drained spellcaster.

Source
This item is conjured by mages using the rank 9 spell Conjure Water. A level 70 mage will create 10 charges per cast. Presumably the number of charges will increase by 2 each level to a maximum of 20 at level 75. This rank is learned from, a drop in high-level Burning Crusade dungeons.