Unicel FS 3053 Rectangular DE Grid Replacement Swimming Pool Filters with Top Exit Port, Full Set Compatible with Sta Rite lighting Jandy 4719 Large 3 Port 2 1 2 Inch best sellers Jandy 4719 Large 3 Port 2 1 2 Inch to 3 Inch Positive Seal Pool Spa NeverLube Valve Frame consists of a flexible & durable TR90 Nylon compound material (material increases "grip" as it becomes moist or warm) which yield an optimal permeability to keep your water sparkling Optimal Performance: Grid cloth design allows for better DE caking properties and less resistance to water flow for optimal performance Longer cycles between backwashes for convenience Efficient Filtration: Filter grid and diatomaceous earth powder paired together efficiently filter out debris and impurities down to an average of 2 to 5 microns Pool Fitment: Compatible with Sta Rite S8D110 System 3