This is a Genuine Pleatco PCST80-EC Spa Filter Cartridge. Pleatco Advanced Point Bonded media advantages: Pleatco point bonded media is uniquely formulated to our specifications Delivers cleaner water by capturing smaller dirt partials Less maintenance - you have longer cycle times between cartridge cleanings Less work- releases dirt fast and easy during filter cleaning Pleatco Free Flow Core: Box ladder design with reinforcing supports, for stability Maximizes water flow Supports lower operating pressures resulting in less wear and tear on pump and equipment Delivers even dirt loading of the media This Pleatco Filtration Spa Filter Cartridge is a direct replacement for the following products: Unicel: C-5396 Filbur: FC-2975 Additional Applications: 817-0098, Coast Spas Top load (in-line) 100, Waterway Plastics Filter Specifications: DIAMETER: 5.375", 136.525 mm LENGTH: 21.3125", 541.3375 mm TOP HOLE SIZE: 2.125" BOTTOM HOLE SIZE: 2.125" MEDIA SQUARE FEET: 80 MEDIA WEIGHT: 3 oz. Our mission at Pleatco is to deliver clean water so families can be healthy together. The Pleatco Filtration Pool filter cartridge you are viewing has been designed to meet high quality standards and outperform all other filters in the market. Pleatco cartridge filters are engineered to meet or exceed OEM specifications for pool and spa water filtration. The Pleatco Advanced filtration fabrics have been uniquely designed to have the highest fiber count in the industry and deliver the most advanced filtration technology available. The Superbond bands around the filter are break resistant and designed to keep the pleats separated for greater flow and dirt holding capacity. The Pleatco Free Flow Core is our unique design to address strength and maximum water flow. Injection molded box ladder design outperforms drilled PVC type cores. You can buy Pleatco filters with confidence because we are partners with the largest manufacturers in the pool and spa filtration industry. Pleatco Filters are designed, engineered, and tested at our US Pool and Spa corporate office in Kentucky. We are continually working to improve the filtration capabilities of our products and are the selected brand partner for many OEM applications. You can buy our products confidently, knowing that our engineers are committed to designing the best products possible. Our pool and spa filters cartridges are Trade Certified and designed to have a longer service life with less maintenance. You will find a Pleatco SmartTrack number on each filter. This code allows for lifelong product identification, quality tracking and warranty accountability. No other filter cartridge in the world offers this substantial feature focused on true customer support. We don't make the filter systems we just make them work better! You can spend less on a filter but why would you?