Carbon Activated Pre-Filter 4-pack for use with the Germ Guardian FLT4825 HEPA Filter, AC4800 Series, Filter B By Complete Filtration Services

The filter is a great way to extend the life of my HEPA filter. Right after the 4th of July I checked the carbon pre-filter on my air purifier. The particulate matter from all the fireworks near my home had really coated the old carbon pre-filter. It was great to be able to quickly change just that bit to extend the life of my HEPA filter. Its sill important to regularly change the actual HEPA filter, but I feel that changing the charcoal pre-filter really does help to extend it for a short time

Great filters. I love my purifier machine germ guardian.

These came in a plastic bag with holes punched in it. Carbon filters degrade when exposed to air. All the other brands I have purchased come sealed in plastic for storage until opened. I dont think Ill purchase this brand again, because there is no indicator that the filters are fresh when they arrive.

Well if you have to buy filters then this is a good brand. I dont know much about filters however i have used this brand numerous times with no issues. Of course in hindsight i wish i bought a filterless air purifier but in the meantime i will continue to use this product. Yes i will recommend.

I am extremely allergic to dust and these catch a lot of dust in my air purifier. I ought these because after I rinsed out the first one that came with the filter, I really did not want to put it back on.

PRO: Can extend the life of your primary HEPA filter CON: (Not really a con, just an observation): Unless you put yourself on a schedule to replace this PRE-FILTER to extend the life on your HEPA PRIMARY filter, youre probably better off getting the combined product which allows for quick, clean, reliable replacement of BOTH filters at once.

I bought these to replace the outer charcoal pre-filter for the GermGuardian AC4825. The filter is cut to the exact size and it sticks very well to the velcro. The material is at least twice as dense as the original filter so will definitely help to filter out more large particles. However, I do worry that the density of the material will put extra strain on the fan motor. I guess Ill find out. Photos 1 and 2: product packaging Photo 3: Original filter (left) vs this filter (right). Right filter is much more dense. Photo 4: This filter installed on top of HEPA filter (left), original dirty filter (right)

Was able to cut these up to fit in my Holmes hepa old air purifier. I cut these a little larger than the size the Holmes came with so they fit snugly and their are no leaks. The old Holmes is like new.

Exactly what they advertised.

These were cheaper than the other filters offered by other sellers. I cannot say how well they work in terms of the activated carbon absorbing anything but it helps to be able to replace the outer filters when they become dusty. I put them in a 1 gallon zip top bag once I got them to keep them fresh (prevent the carbon from absorbing as much as it would otherwise). On the downside, although the width was correct, the filters are not tall enough so I have to cut one of the others to fill the rest of the filter area.