This system produced gains of up to +14 HP and +17 lbs. x Ft. TQ., as measured on our in-house dyno. This cat-back exhaust system is constructed of 3 IN mandrel-bent 409 stainless steel tubing for maximum strength and durability. This system features a high-flow 409 stainless steel muffler, producing a aggressive sound. Finishing off this exhaust system is a 4-1/2 IN diameter polished 304 stainless steel clamp-on exhaust tip. The tip features an aFe POWER logo plate riveted on for a unique style. This system produces an aggressive sound unleashing all available horsepower and torque. Utilizing factory style hangers this system is a direct bolt-on system, which requires no cutting or modifications for a hassle-free installation. Utilizing state-of-the-art computer-aided design technology, this exhaust system is designed for custom, high tolerance factory fitment. 100% MIG-Welded for race-proven strength and durability. Apollo GT Series 3 IN 409 Stainless Steel Cat-Back Exhaust System w/ Polish Tip GM Trucks 09-18 V6-4.3L/V8-4.8/5.3L GM Trucks 09-18 V6-4.3L/V8-4.8/5.3L