Designed to fit the VW Bug this Tri-Mil Street Sidewinder Exhaust System with a merged header and Dynomax Quiet-Pak muffler is made with 5/16″ thick flanges and uses 1-5/8″ dia. 16 ga. mild steel tubing, It is mandrel bent, mig welded and test fit to ensure optimum quality and performance. This exhaust is designed as a high performance merged exhaust system and cannot be used with stock/aftermarket heater boxes or j-tubes. This exhaust comes with hardware and gaskets to be installed. Remember, if it doesn’t say Tri Mil, you’re not getting the best!