Master Flow Standard 90 Adjustable 3 in. Elbow is used to make turns in runs of round pipe and flexible duct through 90. It has a sturdy galvanized steel construction and is simple to adjust. It is also crimped on 1 end to easily fit into a pipe or other fitting of the same diameter. Ships in 90 position.Used to make angular or gradual turns in runs of pipeAdjustable to any angle through 9030-Gauge, galvanized steel constructionAlways seal seams with building code approved sealant or duct tape not includedAlways insulate ductwork for greater system efficiency and comfort not included