Premium quality: Made of sponge, soft and durable, with good flexibility, not easy to deform or break. Reusable: This foam filter will last longer than your paper cartridges. It is recommended to replace it once a week. It can be easily cleaned and reused many times. Function: The swimming pool foam filter can keep the water clean and reduce bacteria in your swimming pool. Application: Suitable for Intex Bubble & Jetted Pure-spas, replaces type S1 paper cartridge. Contents: 6 foam pool filters. Dimensions: 10.8 x 7.3 cm. Product description Features: Material: Sponge. Color: Blue. Dimensions: approximately 10.8 x 7.3 cm. Drilled hole in the center: approximately 4 cm. Features: Superior quality. Made of sponge, soft and durable, with good flexibility, not easy to deform or break. Reusable: This foam filter will last longer than your paper cartridges. It is recommended to replace it once a week. It can be easily cleaned and reused many times. Function: The swimming pool foam filter can keep the water clean and reduce bacteria in your swimming pool. Usage: Suitable for Intex Bubble & Jetted Pure-spas, replaces type S1 paper cartridge. Contents: 6 pool foam filters. Note: 1. Vacuum packaging, restores its original state when exposed to water. 2. Please remove the filter when hitting the electrode rod, as excessive chlorine will cause the foam to break quickly. Normal levels of chlorine and bromine disinfectant are not a problem and these foams have been tested at normal levels.