*ONE SIZE FITS ALL L.A. SPAS* Replace every 3 months. (old part #FD-51104-25) Aqua Klean® filtration system is the foundation in L.A. Spas water technology and a standard on every model. The Aqua Klean® filtration system allows the water to flow through the filter with no restrictions, unlike conventional filters, which typically use a bypass system to achieve the same amount of flow. With other conventional systems, up to 70% of the water is forced to bypass the filtration. The maximum flow design allows the Aqua Klean® filtration system to filter 100% of the water through the filter for maximum natural purity. The Aqua Klean® filtration system not only incorporates the most innovative filtration system in the industry, but also the most economical filter on the market. The Aqua Klean® filter costs about half the amount of conventional filters. This cutting edge technology provides the most efficient and cost effective method to maximize water filtration. Maintaining your spa is as simple as running your conventional washing machine. The Aqua Klean® filter is designed to be placed in your household washing machine, requiring just a turn of the switch, to keep your spa as Pure as Nature.