RGF's Self-Flushing 1/2 Yard & 1 Yard Solids Collection / Dewatering Filters are designed to remove light and medium solids from the waste stream and collect for disposal. Filters to 170 micron particle size. Reduces labor costs by avoiding the difficult and unhealthy task of cleaning out below grade sump pits. Requires a sump basin to be located under hopper to catch and transfer filtered water.