The size of the humidifier cleaner ball . It is almost suitable for all types of humidifiers, including the following types of home humidifiers and steamers: ultrasonic, cool mist (impeller), warm mist, evaporative, and steam vaporizers. It is also applicable to aquariums(fish tanks). Note: The opening diameter of the humidifier should be at least 1.3 inches, please check if the opening of your humidifier is large enough. Equipped with advanced water softening granules designed specifically to address the hard water issues in humidifiers and fish tanks. This fish device effectively filters and absorbs minerals like calcium and magnesium from the water, reducing scale buildup and white dust, protecting the humidifier and fish tank from damage, and extending the lifespan of the device. By softening the water, humidifier cleaner ball reduces the white dust emitted by humidifiers and fish tanks, helping to improve indoor air quality and providing a healthier living environment for families. Humidifier cleaner's long lifespan, requiring only a monthly replacement. Additionally, Humidifier cleaner saves users on extra maintenance costs by lessening the need for frequent repairs and cleaning of humidifiers. The package includes 16 humidifier cleaner ball, enough for a household humidifier or a fish tank to use for 16 months.