The MULTI-CELL CS-65 filter, sized 18x24x4, is packaged in sets of 3 by Koch Filter Corp. This high-efficiency air filter is designed for optimal performance in various HVAC applications. Its multi-cell construction maximizes surface area for superior dust and particulate capture, ensuring cleaner air. Made from durable materials, the CS-65 filter complies with industry standards for filtration efficiency, making it suitable for both commercial and residential use. Ideal for environments requiring high air quality, the MULTI-CELL CS-65 is a reliable choice for effective filtration.