Humidifier Cleaner - Works in virtually all humidifiers,including the following types of residential humidifiers and vaporizers:Ultrasonic,Cool Mist (impeller), Warm Mist,Evaporative and Steam Vaporizer. Also works in fish tanks. Eliminates Mineral Build-up - The Cleaning helps to prevent and reduce the white-dust caused by minerals in hard water. This hard-water"dust"can contain calcium, or magnesium Purifies Water - Reduces up to 99% of odor causing Harmful substances growth,Keeps your humidifiers mist clean and less tank cleaning times Easy To Use - Simply drop it in tank,for fresh,pure mist. Replace every 30 days.This humidifier tank cleaning ball contains no harsh chemicals Easy installation, more stable performance and effortless cleaning, so you can easily clean every day. Humidifier cleaning ball----suitable for all humidifiers Function: Reduce mineral accumulation, humidifier mold, water pollution and other problems, eliminate white dust and odor, keep your humidifier water mist clean, and protect the health of pets. How to use: Just put it in the humidifier Colour:Blue Material:plastic Package Contents: 15 x Humidifier cleaning ball Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.