Protect your drainage system with a drain grate that lets excess stormwater flow through while blocking out leaves and debris that can enter and potentially clog the pipeline. The 18 in. drain grate fits 18 in. high-volume catch basin drains and is a vital component of any drainage system. Drain grates, also known as drain covers, help keep your drain pipes clog-free and running smoothly. The 18 in. square grate, as part of a complete drainage solution, works with 18 in. catch basins, risers, and low-profile adapters which are connected to drain pipes to carry the water to a discharge point downstream such as a pop-up emitter, or to percolate into the ground with a dry well or infiltration trench. The outdoor drain grate sits on top of the catch basin or riser. The 18x18 outdoor drain grate is made of polyethylene, a type of plastic, treated with UV inhibitors to prevent cracking and fading in the sun. The square catch basin grate has an open surface area of 86.3 sq. in. and flow rate capacity of 264 GPM. The drainage grate is rated for NDS Class B loads (up to 175 psi) when properly installed and is ADA compliant. NDS offers scalable and flexible solutions to help manage stormwater for commercial, industrial, and residential applications. Founded in 1972, NDS is the preferred choice of professionals offering products, tools, and expert support to help get the job done right. Make your project a success with NDS-the leader in stormwater management. Color: Black/Matte.