Product review (5 stars): Perfect Fit For Red Cross Cool Mist Humidifier
This was a direct replacement filter for my Cool Mist Humidifier.  I'm not a big fan of the way this humidifier works, as this filter wicks the water up and the fan blows air through the filter to create saturated air.  This leads to the filter constantly being wet, and therefore, being a haven for mold, mildew, and whatever else likes to grow in cool, dark, wet atmospheres.  However, this filter is a perfect replacement for the unit, and I give it 5 stars, because it's not the filter's fault that it has to be replaced all the time.