Keep your channel drain system running as efficiently as possible with a channel drain grate in place. The 3 in. Pro Series™ Channel Drain Grate blocks leaves and debris from entering and potentially clogging your drainage system and works with the 3 in. Pro Series Channel Drain to drain moderate flows from driveways, patios, courtyards, and walkways. The drain grate, or drain cover, is made of gray polyethylene and has an open surface area of 23.6 sq. in./ft. and 72 GPM/ft. flow rate.