Filtrex FX20 VOC Carbon Block Cartridge reduces volatile organic compounds and contaminants in water systems. It uses high performance carbon block media for efficient filtration. The large 4.5 x 20 inch size supports higher flow and extended service life. The cartridge fits standard big blue housings for easy installation. It ensures steady water flow and reliable performance in filtration systems. This cartridge is suitable for commercial and residential water treatment applications.