The Pleatco PCC130-PAK4 is a complete set of four replacement filter cartridges for the Pentair Clean & Clear Plus 520 model pool filter for 520 square feet. Each cartridge contains an area of 130 sq. ft, all four together totaling 520 sq. ft.Take advantage of Pleatco's Advanced cartridges that are scientifically engineered to provide more thorough cleaning and longer lifespans. Pleatco Advanced media contains more fibers per unit area, offering far greater volume dirt holding capacity than