The AquaRest Filter is a great replacement filter for any and all AquaRest pools and spas. This one-size-fits-all filter is made from top-quality urethane tops and Reemay filter elements to keep your water crystal clear and your spa running properly for years to come. Be sure to read the complete instructions on how to install the cartridge correctly, monitoring your spa"s performance so you know when it"s due for a change. Replacement spa filter. Made from urethane and Reemay filter elements. Fits all AquaRest spas. Ensures crystal clear water and hot-tub longevity.