Replacing the paper filter elements is part of the daily maintenance of your swimming pool, and regular replacement of the will bring a high price. These washable and reusable foam filters can reduce your costs. The initial cost of this is slightly higher than the , but it is still longer than the This foam filter is longer lasting than your carton and can be washed and reused multiple times. It is recommended to change the cartons every week, and these foams can be simply cleaned and put back. You should be to see the foam filter for 2 months. specification: Type: filter sponge Center drilling: about 40mm Colour: blue Material: sponge Size: 10.8 * 7.3 cm Package Contents: 4 * Filter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.