The Germ Guardian GGHS15 can be used in the following types of humidifiers:
The Germ Guardian Aquastick Water Tank Cartridge is a safe and non-toxic way of reducing the growth of odor-causing mold and bacteria in your humidifier's water tank. The Germ Guardian GGHS15 Aquastick Antimicrobial Humidifier Treatment is safe to use in all ultrasonic and evaporative humidifiers and provides 3 continuous months of use. The Germ Guardian Aquastick antimicrobial treatment measures 1.2" x 1.2" x 1.2" and is also known by model number GGHS15.
Germ Guardian Aquastick Water Tank Cartridge specifications: