I got a standard replacement middle box and went to put this on with old one off and wouldnt fit over the cat sleeve completly. Which I beleive measured 2inch so did roughly the bore of the middle box, obviously mm larger or so to fit over sleeve.

The replacement box measured roughly 1inch ¾ a inch after the flange.....so if you still follow me why is it diffrent are there two diffrent bores of cats and two diffent bores of a standard middle box section.

________________________________________

Silver 6