Review on 🌈 Colorfullife Replacement Filters for Holmes AER1 HEPA Type Total Air Filter - HAPF30AT and HAP242-NUC Compatible, Pack of 4 HEPA + 8 Carbon Booster Filters by David Barit

With modifications the pre-filter works as expected with the filter. After some trial and error I found that the pre-filter should not be installed where the original pre-filter was installed. Instead, it seems to work best if you cut off half an inch from the long side and half an inch from the short side, then tuck it under the filter's two horizontal bars. I uploaded some pictures to show you what I did. I found that these changes stopped the annoying whistling noise from the air cleaner when trying to install the pre-filter in the same spot the original pre-filter was installed. and it seemed to reduce the load on my air purifier's motor. They are cheaper than the original manufacturer's product and it only took me a few minutes to fit them to my air purifier. I'm happy to spend a few minutes of my time making the necessary changes to save about $50. I will definitely buy them again.