3" diameter system Contains SwitchFire™ technology & Polyphoinic Harmonizer technology Installation REQUIRES cutting drivers side O.E. tail pipe assembly 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