Installation REQUIRES cutting drivers side O.E. tail pipe assembly 3" diameter system. BORLA® system is a True Dual design Contains SwitchFire™ technology & Polyphoinic Harmonizer technology O.E. tail pipes are Resonance Free pipes to help control drone & resonance (see video) Reuse O.E. Over Axle Pipes & O.E. Tips, or Reuse O.E. Over Axle Pipes & Optional BORLA® Tips