The people complaining about those honeywell filters have air handlers designed to use proprietary filters. I like using thicker ac filters, and the standard 16x25x4 filters don't fit the lennox system in my new house.

The deliberate undersizing creates areas for the air to travel around the filter totally negating the purpose of an air filter. The filter flops around in the holding slot and is not capturing all the air flow. Leaves a gap in the filter holder.

This product is not 4 wide. The actual size is smaller in every dimension. This product states that it is 4, nominal.

The printing on the filter says they are the right size but they are 1-in narrower than a normal 4-in thick filter. These are sub-standard filters based on dimensions. Will stick with full-sized, properly labelled 3m filters from now on.

This filter is not as represented by the manufacturer’s labeling. This means the filtering material could have the merv rating stated (13) but won’t be able to provide it because of the amount of airflow that will run around it rather than through it....  Read More