Marineland Rite Size Z Filter Cartridges - 3 Pack is designed to support clean, healthy aquarium water. The poly-fiber pad mechanically filters water before it's chemically filtered through the Black Diamond Premium Activated Carbon. The patented ribbed backing creates an even distribution of activated carbon and maximum water-to-carbon contact for clearer water. Double thick poly-fiber traps debris and waste particles and lasts for up to 2-4 weeks Slides easily into place making replacement fast, dry and effortless Compatible with Eclipse Explorer, Eclipse System 3, Eclipse Hex 5, Eclipse Corner 5 and Hex 7. Shop Marineland aquarium filters, pumps and filter media at Uncle Bill's Pet Centers for trusted pet supplies and knowledgeable service in Indiana.