BORLA Cat-Back and Axle-Back multi-core technology is designed to unleash hidden horsepower. Increased exhaust velocity adds power, driving excitement, fuel economy, and the distinctive BORLA Sound of Power respected by motoring enthusiasts everywhere. Each system is built from premium T-304 stainless steel, superior to T-400 series knockoffs (such as 409), to give you the absolute best in performance and durability. Ultra-smooth mandrel bends ensure maximum flow & power, and precision computer-controlled CNC manufacturing ensures an accurate fit. Best of all, BORLA stands behind every system with a Million-Mile Warranty. Just what you?d expect from the world?s most experienced (and most winning) exhaust brand. S-Type Cat-Back Exhaust System for 2015-2020 Subaru Impreza WRX/ WRX STI Sedan 2.0L/ 2.5L Turbo 4 Cyl. All Wheel Drive Automatic/ Manual Transmission 4 Door. WRX/WRX STI, SEDAN '15-'19 2.0L/2.5L TURBO AT/MT AWD 4DR 3", 2.25", 2.00" "S-TYPE" D RD RL AC SR CB TIP 3.5" RD X 6" CERAMIC BLACK