Grate Guardian is a Catch Basin Filter designed to remove sediment and debris from stormwater as it enters the catch basin. Simply remove the grate and insert into the one-side opening of the Grate Guardian and replace into the catch basin. The weight of the grate seals the fabric in place, for the most effective above-grate filtration. Unlike inserts, the sediment and debris is captured before it enters the catch basin, making it easier to clean and maintain. It is manufactured with 8 oz. non-woven geotextile, providing a durable filter fabric and high flow rate. The round “doughnut” in the middle of the unit allows overflow access during periods of high flow. Overall, the Grate Guardian is an effective solution for filtering stormwater on the jobsite.