Product review (2 stars): OK, but not the real thing
The vendor should be up front about the fact that these are knock-offs. They fit my humidifier (HCM-525), but are significantly thinner than the Honeywell filters I usually buy. More importantly, they are not bacteria-resistant like the name brand.  After only two weeks of use, they are ready for the trash. It helps to flip them daily, but it's a pain in the butt.
If you're considering buying these to use in the HCM-525 humidifier, you would do better to buy the HAC-514 from the same vendor and cutting them down to size. They are the same quality (so-so), but at least they are thicker and much less expensive, so you won't feel like you paid too much for them.