Product review (1 stars): too soft to stand up
We have had the humidifier that these filters are made to work with for at least six years.  The machine works just fine.  However, we've had trouble finding reliable replacement filters.  And these are the worst ever.  The material is so soft that the filters collapse when they encounter water.  If that sounds strange -- because the product is supposedly "designed" to work while standing half-immersed in water -- your instinct is correct.  This product is a total waste of time and money.