GermGuardian Filter O HEPA Pure Genuine Air Purifier Replacement Filter, Removes 99.97% of Pollutants, Wildfire Smoke, Odors, Mold Spores, for GermGuardian Air Purifier AC5109W, Black, FLT5100

If your Germ Guardian Air Purifier uses this O type/size filter, then you probably like what it does for you. What you may not like is the price once you discover than it is available directly from Germ Guardian for less than $50 USD. Current scarcity of this product may be related to Los Angeles wildfires in progress. I bought the replacement for this (needed every six months) from Walmart because it was the only one available and it was the last one that Walmart had. Once the wildfire season has ceased, if availability doesn’t improve then I’ll look for a different brand air purifier that has a long term record of filter availability. It seems silly and wasteful to have to replace the purifier because of filter being unavailable.