The Big Daddy RD-800 Series dual roof drains from Watts Water Technologies offer leakage protection, durable construction and ease of installation. The drains eliminate the need to cut separate holes in the roof for overflow drainage. In testing, the 10-inch model achieved a 1,368 gpm flow rate. They are available in 8- and 10-inch outlets and a cut-through overflow option is available. 978-688-1811; www.watts.com