Pleatco filter grids are simply the finest replacement grids you can buy for your pool or spa. The Pleatco PFS1836 Filter Grid Set is made of the finest filtration fabric. Its reinforced center tube creates a duct to funnel water from the outermost edges to the center and throughout the entire frame. When using Pleatco filter grids the amount of time between cleaning and servicing is increased. Pleatco filters will reduce the water pressure and increase flow rate, while using less energy than other filter cartridges.