15% increased Flask Charges gained
Mana Flasks gain 1 Charge every 3 seconds
Remove a random Elemental Ailment when you use a Mana Flask 
Essence Extraction is a notable passive skill that grants increased mana regeneration rate and increased flask charges gained. It grants an effect that causes the characters mana flasks to gain 1 charge every 3 seconds. It also grants an effect that removes a random elemental ailment on the character when a mana flask is used.