Essick Air 1970-12 Humidifier, 12-Quart Bacteriostatic Treatment, Pack, Clear Use Only Original Essick Air Bacteria Treatment for Optimal Performance of Your Humidifier Helps Eliminate Unpleasant Odors Use with Evaporative Humidifiers Use to Control the Growth of Bacteria and Algae in Humidifiers 12 -32 Ounce Bottle