Product review (5 stars): Excellent for Humidifiers
This stuff keeps the "Old" humidifier smell from happening. We use a inexpensive Sunbeam humidifier that we have used for years, the problem has always been that a filter does not last very long until you get the moldy smell. With this product the humidifier filter smells new for a long time.

I would recommend this for anyone who needs a humidifier to last and smell good for a while.