Outer Diameter: 9 1/4" Length: 19 5/8" Top Style: 3" Open; Bottom Style: 3" Open; Media: 120 SF Compatible with Hayward C1250 CX1250RE CX1250-RE ASL Full-Flo Pleatco PA125 Unicel C-9499 Pure N Clean PC-1299 Filbur FC-1299 Hot Tub Spa Filter. SpiroPure pool and spa filter cartridges offer long-lasting, durable filter media with high dirt holding capacity for clear, sparkling water in your pool or hot tub spa. A strong inner core means increased strength without hindering water flow or filtration performance. Easy to install, durable filter cartridges that allow for high filtration performance and efficiency SpiroPure SP-PS-1299 Hottub Spa Pool Filter Replacement Cartridge. Easy to install, durable filter cartridges that allow for high filtration performance and efficiency.