They're 3" center in/center out. I paid $110 each. That's alot of cash for a muffler if you ask me! I called around locally and the cheapest place wanted $225 each! So I gladly ordered them from Jegs and choked down the $40 for shipping to Alaska. They weigh a little over 20lbs each. I think I'm going to end up doing what Yukon Jack did (kind of). Running 3" from the headers to the mufflers. And reducing to 2.5" after the muffler.