GI fittings are an essential component of many plumbing and piping systems, particularly those that require durability and resistance to corrosion. A GI (Galvanized Iron) pipe fitting is an essential component in plumbing and piping systems used to connect, control, and direct the flow of fluids such as water, gas, and other liquids within a structure.These fittings are made from Gi steel, which has been coated with a layer of zinc to protect against rust and other forms of corrosion.