Flowtech Headers are the perfect combination of quality and value. These shorty, emission compatible headers fit the popular 02-13 Chevy Silverado/Tahoe/Avalanche/Suburban and GMC Sierra V-8 4.8L/5.3L, 2WD/4WD. Features: Mandrel-bent tubes provide consistent tubing diameters for smooth flow and increased exhaust velocity Heavy duty 16-gauge tubing for increased strength and durability Smooth transition, 1-5/8 diameter primary tubes are used for increased exhaust flow increasing performance and improving throttle response OE style 2-1/2 ball and socket collector connects to factory exhaust head pipe with no cutting or welding TIG-welded, machined 3/8 header flange for a leak-free seal and maximum strength Premium aluminum header gaskets included Coated in a satin silver metallic ceramic thermal barrier coating for an aggressive look and reduced underhood temperatures Headers are a must if you are using a cold air intake, cat-back exhaust system or tuner C.A.R.B. EO# D-115-20