NDS Catch Basin Filter 12 in.. Give your drainage system the power to perform effectively by preventing dirt and debris from slowing it down. The 12 in. Square Catch Basin Drain Filter blocks more particles from entering and potentially clogging your drain pipes than a drain grate alone as it drains excess stormwater away. The polypropylene geotextile fabric filter comes preassembled on a sturdy polypropylene (PP) frame, treated with UV inhibitors. The filter material is engineered to withstand chemicals, alkalis, and acids. The unique bypass feature allows water to continue to flow through the system even when the filter is full.