RN is correct. A "cat back" is mounted in back of the catalytic converter. You only have dual exhaust from there back. True duals split at the headers an go all the back as duels. I have the Borla cat back, installed flawlessly, looks and sounds great. Shop around, you can make a $200 mistake if not careful. See mine at:
http://www.ptcruiserlinks.com/arc/35.html
Dave <><