Replacement filter for rusco INC FS1 sand separator/ sediment Trapper. This replacement Element is manufactured by rusco INC. To be used with Model # FS1. The polyester membrane is offered in 24 mesh, 60 mesh, 100 mesh and 250 mesh. The membrane can be periodically cleaned through the flush valve. Over time The membrane may gradually become loaded or damaged which will require replacement. The exact measurement is 1 1/8 inch OD x 5 1/8 inch length. The 24 mesh membrane is equivalent to 707 microns (0.0280 inches). The 60 mesh membrane is equivalent to 250 microns (0.0098 inches). The 250 mesh membrane is equivalent to 63 microns (0.0024 inches).