Pacesetter Coated Long Tube Headers for GM Truck (PN:72C2265) Fits 99-04 Silverado/Sierra Trucks 1500 2wd/4wd 4.8L/5.3L. PaceSetter now offers quality-made, affordably-priced long tube headers for full-size light duty pick up trucks and SUVs. * CNC-machined 3/8"-thick steel flanges are matched to exhaust port profile for optimum seal and flow. * Flash-controlled 16-gauge carbon steel primaries provide greater durability than light gauge stainless steel. * Length and diameter of mandrel-bent tubing is optimized for flow and best performance increase. * Tubes enter collector in proper sequence for maximum scavenging. * O2 sensor fittings on all applications. * Complete with necessary gaskets and fasteners for installation. * Made in USA * Affordably priced * Off road use only.