All the parts you need for true duals are. the h-pipe, the tail pipes and mufflers for both sides and hangers for the passenger side. The stock pipes have a 2.25" diameter and most aftermarket have 2.5" diameter. Some say this is too big but I love it on mine. I you want my opinion buy a 2.5" flowmaster cat-back system. It is about $300. Go to
www.MACperformance.com and get the V6 h-pipe. Off-road if you can but if you have to pass inspections get one with high flow cats. Then go to your local ford dealer and get the two hangers you need. It took me and a buddy 2 hrs to instal with floor jacks. I am trying to get a sound clip for people to hear of mine. It is decent sounding and got some power from it. Hope this helps.