100% brand new and high quality, reusable foam filter. Suitable for Intex Bubble and Jetted Pure-spas. Replacement for S1 cartridge. Replacing the filter elements of paper filter is part of the daily maintenance of the pool. These cleaning and reusable foam filters help reduce your cost. The initial cost of the cartridge is slightly higher than paper filters, but offers a longer lifespan over time. More durable than paper cartridges, and can be washed and reused multiple times. Size: 10.8 x 7.3 cm Center hole diameter: Approx 4 cm Note: Allow 2 hours for the compressed product to fully expand Color: blue Material: sponge Package Contents: 16 x Filter Sponges Only the above package content is included; other products are not included. Note: Lighting and display differences may cause slight variations in color. Measurement error is +/- 1-3 cm.