Filter works great. I originally bought 4 inch filter since that was what was on my furnace. Turns out that actual sizes vary from manufacturer to manufacturer. After one email to customer service a new 5 inch filter was on its way. 5 inch fit perfectly. Filter works well and customer service was excellent.

I'm very impressed with these filters. They do exactly what say they would! Thank you very much.

First off, the filter width I received was 3 5/8” which is odd since I requested 4” width. Because of this, I am concerned that some air will bypass the filter and go around it since the fit is not snug with a considerable gap. That said, the performance is monumentally improved. I was using MERV 11 or 12 filters from Honeywell and 3M and they both did not capture or filter as much particulate matter as the Colorfil filters do. There is far less dusting to be done AND MOST IMPORTANTLY, the musty odor that used to come through the vents has vanished! My olfactory senses have always been acute and I smell everything, good and bad, that some folks don’t even notice. It was so disappointing that a new home build with upgraded A/C systems would produce a musty, dusty, and sometimes, gym sock odor or allow them to come through. Those stinky days are over and that has been the most valuable feature for us; that removal of all odors. I stand near the vents and breath the air and the cool, forced air, is crisp and clean! Great work y’all! We need to figure out why the odd sizes though, because we intend to use your filters exclusively!

Love how well they clean the air (it even smells better!) and I do not have to worry about when to change the filter, just look at it and KNOW when it is time by the color!