Borla ATAK cat-back exhaust system with active valve exhaust control. tube diameter is 2.75" compared to 2.5" for OEM exhaust. Hear it on the GT350 at Borla's website. Used less than 500 miles, new condition. Includes installation instructions and original buyer warranty registration. Will ship, located Minneapolis/St. Paul area. Paid $1,880 new plus shipping & tax, sell for $1,000.