Product review (3 stars): Cheap quality replacement filter
The price seemed decent so I bought it. I have a Holmes purified cool mist humidifier and the way the type D filter fits in there does not really work great with these flimsy filters. I posted a picture of it. My humidifier has a top plastic piece that  fits on the filter to direct airflow through the filter. These filters are too flimsy for this type of application. I will not buy for that reason, plus they went bad and plugged up about twice as fast as the actual Holmes filter. Just be sure your filter doesn't fit like this one or you might just throw the filters away after struggling for an hour with it.