Premium quality cartridges made of pleated polyester filter media for a long life and high dirt holding capacity Cartridges can be cleaned and re-used in most applications and micron ratings. Specifications Type of filter: Big-Blue Filter media: Polyester-Plus End caps: Plastisol (pliable PVC) Dimensions: 4-1/2" OD x 1-1/16" ID x 20" L Flow rate: Up to 30 GPM (Rate limited by housing used) Micron rating: .35 mic Temperature: Up to 140°F (60°C) (Temperature limits based on pressure and time under load) Applications: potable water, light industrial applications, swimming pool and spa, and well water applications