Prevost Replacement Filter - MFC - Activated Carbon Adsorption FiltrationThe Prevost MFC Filter is an Activated Carbon Adsorption Filer. It filters particles that are 0. 01 m or larger. This is a replacement cartridge filter for the Prevost 3 Stage Combination Sub Micronic Filter. You should replace this filter every 1000 hours or once per year, according to Prevost. Changing your filters regularly maintains the air quality through your system. Switching these filters out is super easy to do; that is part of what makes