It is high quality replacement filter cartridge that gives you clean and clear water for your Softsider Spas, Vita Spas, DM Ind with the top load of 15 square foot. This filter cartridge meets the Unicel # C-4303, Pleatco # PSANT 20, Filbur # FC-0185 and OEM # PVT25 specifications. This 6 ¾ inch long and 4 5/8 inch wide filter cartridge has molded cone handle at its top and 1 9/10 inch wide open hole at the bottom. Very easy to install this replacement filter is made of superior grade of materials.