Fabricate your race exhaust with U and J mandrel bends from Proflow. Crafted from 16-gauge or 18-gauge steel, these exhaust tubing U-bends and J-bends are mandrel-bent to keep exhaust flow high and your performance maximized. Most Proflow U-bends have either 9 or 7.5 legs, while their J-bends have both 3 and 15 legs. If you creating a special-fit exhaust for your race ca then you need these.