We have ceiling return air grills, so it is very important that the sizing is accurate. These filters are 3/16th of an inch in both directions too small, therefore not staying securely in place. We have had to screw them into place. We have also noticed noise, when the furnace runs, which we never had before.
We really like supporting small family businesses. However, we will never purchase these Filterbuy filters ever again. They are smaller than stated and will not stay secure in the return air grill (which is in our ceiling).