This is a 36" long (30" body) x 6" round, 3" id muffler. It has the aluminized case and is fully seam welded. Paid almost $100 for it. It actually sounded awesome as a resonator with performance mufflers behind it, however with the car lowered; I'd have to redesign my whole exhaust to get ground clearance back. The muffler itself has a war wound from a speedbump, but it did not puncture the case and it is not that bad a dent. Obviously I will not get what I paid for it (only 6 months old), but I'm asking $40. This is an awesome resonator, and the only one to use if you want a 3" exhaust that's got a quiet deep rumble. I used this with no mufflers behind it for about 4 months and it sounded pretty good, but a little loud for me.