Product review (1 stars): Not suitable for my humidifier
I chose this item as a less expensive substitute for the Apilaire water pad.  After using it for a few weeks, I ntoiced a puddle of water on the floor around the furnace.  After opening the furnace, I found about a half-inch of water at the bottom of the air return duct and some water inside the furnace.  I removed the water pad from the humidifer and noticed that there was about a 1/2 inch gap between the top of the pad and the bottom of the water distribution tray.  I don't remember whether it was like this when I first installed it ( I think that it was) or whether it may have shrunk or deformed after being wet for some time.  In either event, because of the gap,  if the air flow through the humidifer is strong enough, the air blows the water dripping off the bottom of the distribution tray directly into the air duct instead of allowing it to dtip onto the top of the pad.  Through time, it accumulates at the bottom of the duct and eventually leaks into the furnace and onto the floor.  This product is not suitable for use in an Aprilaire model 440 humidifer.  Do not buy it.  Spend a few dollars more and buy the Aprilaire replacement pad which is a stiffer material instead of this paper-like material and does not have a gap between the top of the pad and the bottom of the distribution tray.