Buschur stuff is top quality - I think their cat does not bolt in

This UR one bolts into other applications such as TX's or Perrin

I made 420 to the wheels on pump gas and now am running at least 500 whp at 2 bars with race fuel with no problems on this cat - I expect to break my drag record this sat with it in the car

 

Just to clarify. I got confused when someone said it bolted to the stock exhaust.

Does the UR cat have 3" flanges or not? I want to use the 3" BR downpipe, will this bolt up directly without any monkey business?

Or am I missing something. Thanks!