Borla Cat-back Exhaust Kit with Dual Tips for the 06-09 Trailblazer SS. BORLA, the original pioneers of high quality, austenitic stainless steel (superior to 409 or aluminized steel) free-flow exhaust utilizes patented award and race winning technology to deliver quality, sound, performance gains and enhanced fuel economy -- all with an easy bolt-on installation. And backed by an unsurpassed written million-mile warranty. The dual tip (PN140206) system requires notching the rear valance to give the second exhaust exit location on the rear of the vehicle. BORLA provides full instructions including a simple template for this operation. When you are finished, you have a super look that people can’t help but notice.