Banks massive 3.5 inch boost tubes are the largest on the market, flowing 26-45 percent more air than stock! Smooth mandrel-bent tubes deliver more air to your engine while reducing boost pressure loss resulting in quicker turbo spool and more power. Banks Boost Tubes are the largest charge air cooler pipes in the industry, measuring in at a full 3.5 inches. Every other competitive product on the market tops out at just 3.0 inches, and your factory pipes are only 2.5 inches with crushed bent corners and flimsy plastic components. By contrast, Banks Boost Tubes are made of high-quality aluminized steel for maximum strength and durability. With Banks Boost Tubes' smooth bends, your turbo can spool quicker thanks to improved boost pressure retention for maximum horsepower.The Boost Tubes work with the stock Duramax intake components by using proprietary high-strength 5-ply silicone hoses. Unique to the 2020+ model, a pair of billet aluminum cold-side adapters are also used for the intercooler connection and the throttle body. These are specially made for the airflow requirements of the L5P and feature a Venturi-like taper on their inside diameter to maintain boost pressure and volumetric flow.