The Amerimax Home Products 2 in. x 3 in. Aluminum Downspout A Elbow is designed for use at the top and bottom of the downspout to guide the runoff away from the wall and foundation of your home. Featuring a baked-on white finish and rust-free, aluminum construction, this elbow can be used to help prevent erosion. This downspout elbow fits 2 in. x 3 in. aluminum downspouts.