When draining moderate stormwater flows from mulched landscape beds, natural areas, window wells, and areas prone to debris, the atrium drain grate rises to the challenge. Unlike a flat grate that lies flush with the surface, the 4 in. Atrium Grate has a raised dome design that blocks leaves, mulch, and other debris near the base, while continuously allowing water to flow through the top. The 4 in. atrium dome drain grate has an open surface area of 21.5 sq. in. and a flow rate of 66 GPM. Connect to 3 in. and 4 in. sewer and drainpipe and fittings, 3 in. and 4 in. single-wall corrugated pipe, and 3 in. and 4 in. triple-wall pipe for a soil-tight fit. Built to stand up to the elements, the drain grate (or drain cover) is made of polyethylene, a type of plastic, using a combination of virgin and recycled content treated with UV inhibitors to prevent fading and cracking from the sun. As part of a complete drainage system, the grate drains water entering drainpipes. The pipes 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. Start now and find the right drainage grate for your project with the free NDS Home Drainage Center tool. NDS, founded in 1972, is the preferred choice of professionals and the leader in stormwater management solutions with proven products, tools, and support to help you get the job done right. Color: Black/Matte.