The Intex 29001 Filter Cartridge comes in a twin pack and is designed for use with Intex PureSpa bubble therapy and jet massage systems. Constructed from heavy-duty Dacron paper, it ensures superior filtration. For optimal performance, its recommended to clean the cartridges weekly and replace them monthly or as needed. Material: Polyvinyl Chloride (PVC) Dimensions: Length 15.2 cm x Width 11 cm x Height 11 cm