Effectively make angular or gradual turns in ductwork with the Imperial Round Adjustable Elbow. Adjustable from 0 to 90 degrees, the elbow is used to change the direction of airflow in round branch pipes. It is ideal for use with all heating, venting and air conditioning where rigid pipe is required. Made from 30-gauge galvanized steel, this elbow offers lasting durability. Easy to install, the elbow has a 4-in diameter and features one crimped end for a secure connection into a pipe or other fitting of the same diameter.