Product review (5 stars): A great option, comparable to original filters
We use one filter for 24 hours, then let that one dry overnight while we use another one. These filters have lasted pretty well in that set up (still going strong after 4 weeks). After soaking it holds its shape well. It seems to have plenty of layers, and it is comparable to the filters that came with the humidifier. I've included a comparison photo of&nbsp;<a data-hook="product-link-linked" class="a-link-normal" href="/Honeywell-HAC-504-Series-Humidifier-Replacement-Filter-Filter-A/dp/B000RDAORO/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Honeywell HAC-504 Series Humidifier Replacement Filter, Filter A</a>, the original filter included with my Honeywell HAC-504 Humidifier, and this one. You can see in the photo how similar it is to the original (height, how much they spread out, etc.). I will buy these again.