Changing your paper filter cartridge is part of your routine maintenance for your pool and regular replacement of the cartridge can prove costly. These washable and re-usable foam filters will reduce your costs.Initial cost of this cartridge is slightly more than a paper cartridge yet will outlast a cartridge by a This Foam filter will outlast your paper cartridges and can be washed and re-used several times over.Advises changing a paper cartridge each week, whereas these foams can simply be washed and put back.You should see a foam filter last around 2 months.Specifications:Type: Filter SpongeSize: for S1 TypeColour:BlueMaterial:SpongeSize:10.8 x 7.3 x 4cmPackage Contents:15 x Sponge coreOnly 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.