Pleated Design: The pleats increase the surface area of the filter which enhances its ability to capture more airborne pollutants. Contaminant Removal: It effectively removes various types of contaminants including dust particles, pollen and mold spores from the air. The ILC - NP FILTER-3938 is a Replacement Pleated Air Filter, falling under the category of "Pleated Air Filters". HVAC System Performance: Regular replacement ensures optimal performance of your heating and cooling systems.