This Cartridge is Offered in Multiple Media Types and Quad Packs (4pk) 3oz Reemay - Silver Series (17-175-2127SS) Point Bonded - (17-175-2127PB) 3 oz Reemay - Silver Series - Quad Pack (17-175-2127SS-Q) Point Bonded - Quad Pack (17-175-2127PB-Q) Reemay is Spunbound Polyester made with a continuous filament construction to minimize fiber migration that adds strength and there are no binders to limit filtering area. It is offered in a 3 and 4 ounce media. Look for the "SS" following the Horizon part number for 3oz Reemay cartridges. Point Bonded is a uniformly bonded media. Reduced pore size distribution offers quick cleaning and superior dirt holding capacity with lower pressure and higher flow. Look for the "PB" following the Horizon part number for the Point Bonded cartridges. Look for the "-Q"following the Horizon part number for Quad PacksPlease see the Recommended Items for all media type options.Please see Exploded Diagram tab for compatible models.