AEM Cat Back Exhaust. They provide performance and power with a sporty sound. They are designed to enhance the use of aftermarket air intake systems and like AEM air intake systems they are designed to perform for the life of your vehicle. The system's exhaust tips have an OEM look and quality. AEM Cat Back Exhausts maintain clearances to critical systems and use OEM routing paths when possible, providing a performance exhaust with OEM fit and finish. 1 3/4" B-pipe and 2" Tailpipe. Dyno proven to give 2.3hp and extra torque over the original system. To fit Honda CRZ 10-14 1.5L.