1 Filter Tank Cord O-Ring. Compatible with Pentair part number 24850-0009. Compatible with Pentair Sta-Rite System 3 Filters, including models: S8S70, S8D110, S8M150 and S8M500. ??This O-Ring will not fit “7” series tanks. It will only fit “8” series tanks. For example, if you own a S8M150, S8D110, S8S70 or any other “8” series filter, they require this 25" diameter O-ring (24850-0009). However, If you own a S7M120, S7MD60, S7MD72 or other “7” series filter, they require a different 21" diameter O-ring (24850-0008).?? Alternate part number includes: O-486. Made from heavy duty materials for durability and performance. Replacing the cord ring can return your swimming pool or spa filters to peak performance. The brand names and logos are the registered trademarks of their respective owners. Any use of a brand name or model designation for this product is made solely for purposes of demonstrating compatibility. Packaging may vary.