Replacement Filters Unicel PG1902 Partial Grid Element (12") 24 Sq Ft for Hayward, Sta-Rite, Jacuzzi D.E. Filter Unicel PG1903 Partial Grid Element (18") 36 Sq Ft for Hayward, Sta-Rite, Jacuzzi D.E. Filter Unicel PG1904 Partial Grid Element (24") 48 Sq Ft for Hayward, Sta-Rite, Jacuzzi D.E. Filter Unicel PG1905 Partial Grid Element (30") 60 Sq Ft for Hayward, Sta-Rite, Jacuzzi D.E. Filter Unicel PG1906 Partial Grid Element (36") 72 Sq Ft for Hayward, Sta-Rite, Jacuzzi D.E. Filter