Defend your drainage system by preventing leaves and debris from entering and potentially clogging drain pipes with the trench drain grate. This galvanized steel drain cover has a mesh design and boasts an open surface area of 152.0 sq. in. per meter, and an impressive 465 GPM flow rate. Rated NDS Class B when properly installed; also ADA compliant. One 1-meter (39.37 in.) grate covers one BG-FILCOTEN 100 4 in. trench drain; also available in a 1/2 meter (19.69 in.) size.