2005-2009 Ford Mustang GT V8-4.6L, Tube Size 1-5/8" O.D., Collector Size 2-1/2", Black Paint, CARB EO D-115-19;50 state legal; High flow, mandrel-bent tubes provide consistent tubing diameters for smooth flow and increased exhaust velocity; Heavy duty tubing and high quality welds for increased strength and durability; Smooth transition, 1-5/8” diameter primary tubes are used for increased exhaust flow increasing performance, improving throttle response and broadening the torque curve; 2-1/2” collector used for high tuck design and maximum exhaust component clearance; Machined 3/8” header flange for a leak-free seal and maximum strength; Premium aluminum header gaskets and installation hardware included; Heat resistant black paint for a stealthy look; Shorty header design mounts to factory exhaust system; Accommodates all emission control devices;