BO OBX Performance Exhaust Header Manifold 71-79 AMC 290 304 343 360 390 401 8Cyl Dog Leg Port Precision CNC machined flanges with TIG and MIG welded construction Dyno Proven Increase Low End Torque And Horse Power Mandrel bend for ultra fast and smooth flow Header Gaskets and Hardware included as shown Lifetime warranty from manufacturer defects