Easily and conveniently move damaging rainwater away from your foundation with the Amerimax Flex-A-Spout? Downspout Extension. The rigid corrugated design easily bends and flexes around corners and landscaping while holding it s shape. This versatile downspout extension is designed to fit 2 x3 or 3 x4 downspouts and extends up to 55 in length. If additional length is needed simply cut along the noted lines and attach additional Flex-A-Spout units together for more length.