Unicel C-7466 | 65 sq ft Sundance Spa Filter Cartridge

The Unicel C-7466 is a 65 square foot replacement cartridge for Sundance and Sweetwater spas, replacing OEM part number 6540-481. It carries 164 pleats across a wide 7-1/2" body, and it is distinguished by a closed castle top — a sealed end cap with a crenellated rim, notched like the battlements on a castle wall, which is where the name comes from.

That closed top is not decoration. It means water has exactly one way out of this cartridge: down through the core and out the open bottom into the suction line. On a cartridge with two open ends, water can exit either way and the filter simply sits in the flow path. Here the cartridge is committed to a single direction, and the castellated rim locates it in the housing so it stays centered and square while that flow pulls on it. The notches let water move freely around the top of the cartridge rather than letting it dam up against a solid rim.

The practical case for this cartridge is capacity in a wide, relatively short package. Sixty-five square feet from a body just 14-3/4" tall is achieved through diameter rather than height — the 7-1/2" width gives roughly 23 inches of circumference for those 164 pleats to work with, so the folds can stay generously spaced. That matters more than it sounds. Widely spaced pleats release trapped debris far more readily during cleaning than tightly packed ones, which means this cartridge recovers closer to full performance after each wash and holds that recovery over more cleaning cycles.

Media is Unicel's standard 3 oz Reemay polyester — one hundred percent spunbonded polyester over a solid injection-molded core, with chemical-resistant end caps molded to an exact OEM fit, capturing suspended particles down to roughly 20 microns. Made in the USA by Meissner Manufacturing, with more than 45 years behind the Unicel name.