Replacement Cartridge Filters EO4791 Environmental. Replacement Element for Part Number Environmental EO4791 Filter. 12.75" OD x 30" L(Cage) 80/20 Blended sq ft media. Environmental is a registered trademark of the respective company. TDSF-10002251 Replacement Cartridge Filters EO4791 Environmental.Our Replacement filters Work As Good Or The Same As The OEM Filters. We guarantee their performance. Some of the filters are non stock items and cannot be returned. Please see our return policy.