Blue Pure 211+ Blue Washable Pre-Filter, Removes Pollen, Dust, Pet Dander and Other Airborne Pollutants, Diva Blue, by Blueair

After a couple of changes, these external pre-filters are very easy to install. You should have at least one in addition to the one that comes included with the unit. They filter out pet dander, etc. and prolong the life if tge main carbon filter inside the unit. To clean them, just throw them in with the regular laundry for a cold water wash. Many colors available to augment your decor.

I like this fabric trap, it collects a lot of dust and other airborne pollutants. It protects the inner filter so it stays cleaner longer. Twice a month I vacuum the exterior of the unit and the fabric after first unplugging the unit. Approximately every 3 month, I unplug the unit, release the upper section from the lower part and remove the fabric and replace it. I machine wash it and lay it on a drying rack to dry.

Works great, easy to replace.

Last year was horrible because of all the wildfires. We couldn't open our windows as the air quality was dangerous. We had to change our AC filters almost monthly. This filter system was so amazing. It kept our home free of the disgusting smoke smell from outside. Three different levels of operation. We placed in the hall of our 2600 sq ft home and it worked well. We did have to change the internal filter in the fall after the fires subsided. The external filter is machine washable.

What can I say, as it does what it's supposed to.