I’m assuming he is speaking about the angled pipe coming off the muffler in the termignoni pic. It is a slip fit, adapter into the muffler. Slip-on mufflers use that short piece, full system uses a longer pipe.
Either I am going crazier or never noticed . ..
IIRC, the ONLY part I could take off the Termi mufflers was the baffle and usually was asked to throw them away . . .