Rite-Size Eclipse Filtration Systems Cartridge 12 Total Cartridges (4 Packs with 3 per Pack) Marineland Rite-Size Cartridges (Size G) There's a Rite-Size cartridge for every Penguin, Emperor, and millennium power filter Color-coded packaging ensures fool-proof cartridge selection Is designed specifically for horizontal placement in our extensive selection of Eclipse systems Delivers crystal clear, crystal clean water