2.5 "exhaust flange (4 bolts) to 2.5" V-Band Material: cast iron Allows for a simple construction of a high-flow exhaust system. Properly selected shape of the housing allows you to accelerate the flow of exhaust gases. Exhaust Flange 2.5 "(4 bolt) for 2,5 "V-BandMaterial: cast ironIt allows for the simple construction of a high flow exhaust system.Appropriately selected housing shape allows acceleration of the exhaust flow. Band Allows for a simple construction of a high-flow exhaust system Properly selected shape of the housing allows for faster exhaust gas flow. Material: cast iron