Galvanized elbow is a type of elbow with a zinc coating applied to its surface to enhance its corrosion resistance. It is available in two types: hot-dipped galvanized and electro-galvanized, with the former having a thicker zinc layer and the latter being more cost-effective but with a less smooth surface. Galvanized elbow pipes are categorized into cold-dipped and hot-dipped, with the former being banned and the latter still recommended by the state for temporary use.