Smilfil 5 Pack PF40 Replacement Pre-Filter Pads Compatible with IQAir PF40 Coarse Dust Pre-Filtration Air Purifier

I have purchased these filters several times. They are the pre-filter that goes on the bottom of my IQAir Air Purifier. I change them out every 2 to 3 months and they help save the life of the larger IQAir filters. They fit my machine perfectly. Installation takes less than 2 minutes and is a breeze. They go on the bottom outside of my purifier where the airflows into the machine. This filter captures the dust and larger particles before they reach the inner filters. So they are an absolute necessity IMO. The airflow is not inhibited in anyway. Great value for the money. I highly recommend them. ⭐️⭐️⭐️⭐️⭐️ experience.

This is my second order. I ordered the 5 pack because it's a much better value. I removed all the filters and placed one of these filter inside on the bottom then I reinstalled the unit filters. These filter the larger particles so that only the smallest particles need to be filtered. Seeing what the filter looked like after I removed it, after a few months, sold me on them. I will continue to purchase them, I just wish they were cheaper.

Arrived in a clear casing, no logo no text, just the filters, Very thin, they said its 19 mm thick but what I got is 6 to 10 mm (each a different size). Looks really low quality, I'll return it.

The IQAIR brand might be better, but they are SO expensive. These are reasonably priced and their performance is satisfactory.

We have dogs and cats that shed their hair consistenly. We needed something to pre-filter out hepa filter to allow the main filter to not clog with pet hair so fast. I did have to use zip ties to secure it but it works well. Will purchase again as needed.

Great as an extra level of filtration which also serves to extend the life of your main filters.

The quality of these filters seems comparable to the original IQAir filters, but there's a major issue: these are only half as thick as the originals. This creates a gap on the side of the purifier due to a flaw in the purifier's design. The original, thicker filters effectively seal this gap, allowing air to be filtered from both the sides and the bottom. These thinner, generic filters barely cover the gap, which can result in air bypassing the prefilter entirely—defeating the purpose of using these coarse filters. If this company produces filters with the same thickness as the originals at a competitive price, I’d recommend them. Until then, I’ll stick with IQAir’s original filters (5 for $60). The IQAir system is a significant investment, and I’m not willing to risk its performance or longevity with subpar filters.

I’ve got four in air multigas units, and these look and work just like the originals. There is no chemical smell to them in my opinion,