Product review (1 stars): Doesn't absorb water well at all.
I've tried several brands of the "E" filters for my humidifier.  This is easily the worst of the bunch.  Not as many layers, not as absorbent.  After I soaked it in water for an hour, installed it, then flipped it over 12 hours later, the top 2 thirds of it was bone dry 12 hours after that.  This is with the fan on low.  Hardly used any water from water tanks. Really poor quality.