Product review (1 stars): Only good for two weeks!
I waited a while to write this review, and I'm glad I did.  The filter worked great for about two weeks.  After that, the humidifier indicated the filter needed replacement.  I checked the filter over and any part that was more then an inch above the water level was totally dry.

I took the filter and tried washing it out in the sink. This gave the filter almost one full week of good use again.  The drying out then happened again, so I repeated the wash/scrub.  This time it didn't even last for two days.

If I want my humidifier to work with this filter, I have to wash it and soak it multiple times a day!

My original filters would last all season without any problems.  I thought I was going to save a few bucks with these, but I guess I learned my lesson.  Don't bother buying these filters!!!