NDS 662 24" Green Channel Grate fits with NDS Dura Slope Channel Drains. This grate helps to collect and remove excess water from driveways, patios and any other outdoor areas, designed for for medium-duty pneumatic tire traffic, autos and light trucks at speeds less than 20 mph, Class B Load Rating: 61-175 psi. Open surface area 20.61 square inches per foot, 27.00 GPM per foot. ADA Compliant NDS channel drains are a proven alternative to traditional concrete drains with UV inhibitors are used to prevent fading and cracking from the sun, chemical-resistant, rustproof and maintenance-free, lightweight and easy to install.