50 SQ FT Threaded FilterThis spa filter offers 50 sq ft of genuine Reemay material, helping to keep your spas and hot tubs cleaner for longer. This filter replaces the following models; Unicel 6CH 940, Filbur FC 0359, Pleatco PWW50P3, and Aladdin 14510. NOTE: Filters should be changed every 4 6 months (depending on usage). For best results, clean your filters regularly using Canadian Spa Company's filter free cleaner solution. 50 sq ft filtration surface area 1 1 2 in SAE