Get the most out of your Subaru WRX or STi exhaust with a Invidia N1 Racing catback. The N1 catback for the WRX and STi features 3 inch fully polished stainless steel, and no resonator for optimal flow. This exhaust system is computerized mandrel-bent for the straightest possible line. Invidia Racing version gives your WRX/STi a very aggressive sound, but is also very loud. This system is louder than Invidia's G200 and Regular N1 catbacks. The Invidia N1 produces strong mid to top end power, as well as an increase in horsepower and torque.  When combined with the Invidia Catless Downpipe you can see great HP gains.  Invidia's Racing N1 catback is a direct bolt on exhaust system and includes a silencer to help reduce noise.