Airborne dust, debris, and dirt can sometimes find their way into your Port-A-Cool, restrict airflow, and affect the unit’s cooling efficiency.Therefore, regularly replacing the filters in your evaporative cooler with thePAC-FILTER-48 filter kit ensures maximum performance. These filters are specially designed for the 48 inch Port-A-Cool units and trap particles before they reach the Kuul™ cooling media. This results in cleaner pads, longer pad life, and even increased efficiency!The PAC-FILTER-48 includes three filters and is compatible with the PAC2K482S and PAC2K48EP 48 inch Port-A-Cool evaporative coolers.Note: The filter frame is not included and must be purchased separately. Port-A-Cool® Evaporative Cooling Units are Manufactured by PORT-A-COOL, LLC., Center, Texas U.S.A.