Review on GermGuardian FLT5000 Carbon Filter for AC5000 Series Air Purifier - 4 Pack by Keith Wolff

This activated carbon pre-filter is perfect for my Guardian Technologies AC5000E. Easy to replace my obviously dirty pre-filter. A 4 pack is especially handy as I have several AC5000Es at home. However, there is a reason for the 3 out of 5 stars. The first thing that struck me, and the main reason for the lower rating, is how thin the pre-filter is compared to the existing pre-filter that originally came with the AC5000E. Now I didn't use a caliper or ruler to measure. If this bothers you, I sincerely (?) apologise. But only when touched, these replacement filters are about twice as thin as the existing activated carbon filters. Second, there is no Velcro to attach the pre-filter to the HEPA filter. The existing pre-filter is attached in several places with Velcro, which I only noticed when removing it for replacement. The lack of Velcro doesn't seem to affect the AC5000E's performance. It will not slip off after 3 days of use. Given the above, I'm really surprised that this is a genuine replacement for Guardian Technologies' Activated Carbon Pre-Filters. It's almost like a third-party replacement due to its fragility and lack of Velcro. But in the end it fits. It works. never mind 3 out of 5 stars.