1 Inch Rusco Spin-Down Sand Separator Replacement Filter Screen FS1-RE Replacement Filter for Rusco Inc FS1 Sand Separator / Sediment Trapper. Over time the membrane may gradually become loaded or damaged which will require replacement The exact measurement is 1 1/8 inch Outer Diameter x 5 1/8 inch length. Includes only the 100 mesh high impact, molded polyester filter screen - 152 microns