This 2.25" True Dual BORLAÂ Cat-Backâ„¢ system was designed specifically for the Frontier equipped with 3.8L engine. The muffler contains an internal H-Pipe for increased performance and improved sound. The system features an upated version (compared to 140919) of the classic S-Type sound that delivers a powerful performance sound with no drone. It features 2 full Tail Pipes (Not a single tail pipe with dual tips) and a single 4" round bright chrome on T-304 stainless steel tip on each tail pipe. A system is also available with black chrome on T-304 stainless steel tips. A High Clearance Climber / Rock Crawler system is also available. BORLAÂ Cat-Backâ„¢ & Axle-Back exhaust systems feature patented straight-through and multi-core technology to unleash hidden horsepower. Increased exhaust velocity adds power driving excitement fuel economy and the distinctive BORLAÂ Sound of Power respected by motoring enthusiasts everywhere. Each system is built from premium high-quality T-304 austenitic stainless steel superior to T-400 series knockoffs (such as 409) to give you the absolute best in performance and durability. The entire system is made of T-304 stainless steel and utilizes computer numerical control (CNC) manufacturing techniques that ensure an accurate fit. All this is backed by our unsurpassed Million Mile Warranty.