AFE 49-48057 MACH Force-Xp Hi-Tuck Cat-Back Exhaust System for 07-18 Jeep Wrangler JK (3.6L & 3.8L V6). This cat-back exhaust system is constructed of 2-1/2" mandrel-bent stainless steel tubing. The smooth curves and increased diameter of this exhaust system helps remove restriction and keeps exhaust gas flowing smoothly for increased horsepower, torque and throttle response. This exhaust system also comes complete with a 18" length high-flow straight through designed muffler to absorb high pitch tones producing a powerful sound.