Keep underground drain pipes that you can’t see clog-free and running smoothly with National Diversified Sales 1881 18" Black Plastic Square Atrium Catch Basin Drain Grate in place. The drain grate blocks troublesome leaves, mulch, and other debris around the base, preventing them from entering and clogging the pipeline, while the domed grate continues to drain water from above. Ideal for draining heavy flows from mulched landscape beds and natural growth areas. The 18" Square Atrium Catch Basin Drain Grate, also known as a beehive grate, is compatible with 18" square catch basins, risers, and low-profile adapters. Made of high-density polyethylene (HDPE) treated with UV inhibitors. Hassle-free limited lifetime warranty guarantees the NDS product is free from defects—or we’ll replace it.