[Sponge Pool filter type H]Length:10 cm/3.93 inch; Outside Diameter: 9 cm/3.54 inch; Inner Diameter: 3 cm/1.18 inch. The pool filter sponge is suitable for type H pool filter pump, It is designed for filter pump. [Reusable washable filter] This Sponge pool filter sponge cartridge is made of high quality material. Replacing the filter paper filter is part of the daily maintenance of the swimming pool. Regular replacement of the filter may high costs. These washable and reusable foam filters will reduce your costs. [Good for your pump]: the sponge filter accessory will help to clean particles and debris so it can prolong the life of your filter media, providing efficient water with less clogging for long lasting filtration and cleaning. [Durable] Regular cleaning two weeks makes the foams more durable. The replacement time depends on the frequency of and the actual situation of the sponges, normally it may last not less than . [Save time and effort]Changing the pool filter cartridge is part of regular maintenance for pool,this reusable washable hot tub tool is much easier to clean and maintain than paper filters,save you lots of time and effort color:Blue Material:sponge Package Contents: 8 x filter sponges Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.