Cot PEHD Rainplus 75/45° Cot PEHD Rainplus 75/45° is a high-performance roof drain system designed for use in residential and commercial buildings. It is made of high-density polyethylene (HDPE) and has an integrated slope of 75/45°, allowing for effective runoff of rainwater. The system also features a special flap valve that prevents water backflow and a filter basket to keep debris out of the drain. It is available in various sizes, colors, and configurations to meet a variety of needs.