Features: The sponges are made of non-polluting material, it will not pollute the water. These washable and re-usable filter sponges will reduce the costs of maintaining your pool and achieve the better cleaning effect. Our pool filter sponge cartridge nicely removes the debris from whatever passes through it, durable and flexible, easy to wash and restore without deformation or damage. The replacement time depends on the frequency of use and the actual situation of the sponges,normally it may last not less than 1 month. Specification: Material: PU sponge Size: 20 cm/7.87 inches long, outer diameter 10 cm/3.94 inches, inner diameter 4 cm/1.57 inches Color: blue Package includes: 6 x Pool filter foam sponges Quantity and size: you will receive 6 pieces pool filter sponge cartridges in blue color, each pool filter sponge cartridge measures approx. 8 x 4 inches/ 20 x 10 cm, fits for most filters,Compatible with Type A Cleaning Replacement Reusable:This Foam filter will outlast your paper cartridges and can be washed and re-used several times over Pool Filter Cartridge:pool filter sponge replacements can be compatible with Type A foam filter, spa swimming pool, bathroom, fish tank and so on Easy to Care: Changing your paper filter cartridge is part of your routine maintenance for your pool and regular replacement of the cartridge can be quite labor costly. is washable, easier to clean and maintain than traditional paper filters Economical and Harmless :The sponges are made of environmentally friendly material, it will not pollute the water as well as the environment,the replacement time depends on the frequency of use and the actual situation of the sponges, normally it may last not less than 1 month