Bassani Xhaust Dual Exhaust - Straight Mufflers174835900 Product Description Features 16 gauge steel construction throughout 1 3 4" headpipes flow into 2 1 4" muffler bodies for increased flow and improved performance Designed to increase low end torque and produce a deep, throaty exhaust note Includes heat shields for the headers, mounting brackets, hardware, O2 sensor ports and plugs Made in the U. S. A. Notes Includes 12 mm and 18 mm O2 sensor ports