Better than low-cost substitutes

I have purchased other, low-cost pre-filters and they are simply not as thick (and thus effective) as these Filtrete pre-filters.

Great for above stove microwave units.

I wanted a filter for my microwave that is above my stove and has a fan in it. Without a filter the fan component just moves the smoke and smell around the room. This was VERY easy to cut to fit and should help reduce unwanted smells in my kitchen

Home made room filter

Cut and attached to 20" box box fan to filter smoke and works great.

3M filters

Able to use over a wide range of pre filter sizes in Air purifiers

Does the job

Filter quality was much better than what originally came with my air purifier.

air filter - filter

Easy to cut and install but wish my store would have had the A2 size filter for my unit.

Works as advertised.

Easy,cut to fit,sheet of carbon material. I was able to use this one sheet to cut multiple size A and a single size A2 filter. Only problem I had is that none of the packages on the shelf had the "provided adhesive clips". So I had to use small pieces of double sided tape to attach it to the filter. Only 4 stars due to missing pieces.