Both ends fit perfectly onto existing exhaust pipes, had to purchase 2 1/4" and 2" clamps. I had to turn the rear clamp down to get a tight seal, but there were no leaks in the end. Since it came without a protective box, the inlet end was slightly dented so I had to knock it out to round it out. fits on the pipe coming from the catalytic converter. The motor also fits perfectly in the rubber mount. 1999 Jetta GLS 2.0