does it replce the 2nd cat on my 01 ES? I looked at the pictures on RB site, but I can't tell. What I did see was a resonator.

Also, what size piping is it? and how does it sound compared to the MS muffler? The MS muffler is kinda loud!!

 

The Racing Beat is a cat-back, so you would keep your cats. I believe the piping is 2.375 in. And it's a quiet system, not loud at all.