The IE Catback Exhaust System for your Audi B9/B9.5 S4 incorporates our in-house engineered DroneTrap technology to deliver a truly aggressive exhaust note without any annoying drone or rasp. Engineered with cutting-edge design features, including mandrel-bent stainless steel, TIG welding, multi-point reinforcements, and oversized quad tips. Experience the elevated and enriched sound your S4 deserves.

Features:

• DroneTrap Technology  -IE's proprietary no-drone resonator design
• Bolt-on direct fit -No cutting, no welding, no hassle
• Aggressive look -Large 90mm slash-cut quad tips
• High-flow design -Dual 2.5" piping to support any power output
• Reliable engineering -Leak free, stamped, & multi-point reinforced
• 50 states legal -No check engine light & emissions compliant
• Optional midpipes: Want to take your catback to the next level? Add a set of IE Midpipes for an even larger boost in sound. By upgrading this section, you'll remove the two factory resonators and 12 feet of exhaust piping, further improving exhaust flow and acoustic notes.
  
  Midpipe upgrade is optional, and the catback can be installed with either stock or IE midpipes.

What's Included:

• Integrated Engineering Catback Exhaust