NDS 3” black round grates are one piece injection molded from structural foam polyolefins for maximum strength. Ultraviolet light inhibitors are added to prevent fading and cracking from exposure to the sun. Grates are engineered to fit various sewer and drain pipes and fittings as well as NDS Spee-D basins. ADA compliant / heel-proof. Fits 3" Sewer & Drain Pipe & Fittings. Recommended For Pedestrians, Bicycles, & Wheel Chair Traffic.