Bought 1 4" airfilter that ended up being 5". Thought it was a fluke and took it back to the store. Went to another store and the only brand availabel was 3m again. Bought a 4" filter and once again measuring in at over 4.5" and does not fit. Last time I buy from 3m. Btw our furnace can fit 2, 2" filters perfectly but not 1, 4".

I have a household of 6 and all my children suffer with seasonal allergies. The great thing about this product is as soon as I change my filters my children feel relief within the day until the next time for change from their allergies. Also like clock work, when the filter is near time for change my children allergies will act up to remind me I need to change the filter. I have no complaint with this product! ;)

I've been using this type filter almost 3 months, and I've got to tell you that it's a great improvement over reusable filters that I was using. You can see all of the particles it collected...yes, it is DIRTY! I couldn't really see the dirt on the washable ones. I've noticed that there is less dust collecting in the house' big plus! Haven't noticed reduction of airflow nor higher energy bills. I'll continue using this filter...a little expensive to me- but we'll worth it!

Upon advice from my doctor to purchase a better a/c filter, I researched and purchased two of these. We quickly noticed a difference in the air quality, my headaches and sneezing are much better now. I am allergic to dust mites and my cats dander - I am extremely impressed. When I clean, there is far less dust accumulated on surfaces in my house which is lovely. After changing the filter recently we found out why - this filter is blocking everything. So great! We are considering investing in higher grades of the Filtrete brand because this one has done so well.

I used to use those half-inch wide throw-away $2 fiberglass filters on my old furnace. But when I invested in a high efficiency furnace, I decided to go with better air quality in the house, too. Boy did I get it. My Filtrete 4-inch wide furnace filter traps a lot of stuff I don't want in the furnace, no less the air I breathe. I have a dog, and though I keep her groomed, there is still dog hair left over; the filter is doing a great job filtering out dog hair that would otherwise enter the furnace air supply. It's a comfort knowing my home is a little cleaner and the air is a lot more breathable with a high quality Filtrete filter.

[This review was collected as part of a promotion.] I love everything about this filter. It does an amazing job, it's easy to install, it comes in the hard-to-find size that I need, and the optional email reminders that it's time to change the filter make life easy and healthy.

My HVAC of 30 years brother told me to purchase these filters vs the little 5 pack ones in order to cut down on the allergens and dust in the house. Monthly I would always change the cheap ones too, but let me say that this Filterate filter is really helping our allergies and furniture dust. I plan on always using them now but often the local is sold out of them. But eventually I get one. I like that there is an area for you to write the installation date on the filter and then take the provided sticker and stick it to your calendar for follow-up.

I live in Michigan and my 2 furnaces run constantly. It is extremely important to me that my family breathes clean, dust/allergen free air. Plus, it makes house cleaning so much easier. The filters are high quality, easy to use and I only have to change them once a year. I wouldn't buy any other brand. Filtrete whole house filters work!

I use 16x20x4 inch MERV 12 filters from Filtrete because they have the best build quality of all the filter brands I have used. I just have an issue with the vague MERV rating for a particular filter. Filtrete uses their own rating system (1550 for example) and then I have to do some research to find the MERV rating.

We purchased this filter for the first last year. It is an amazing filter. Product does a great job filtering out dust in our home. You can actually see the difference in the minimal amount of dust in the house. It's a great product. Would recommend to any body needing a filter.