Also, I should he worded it better. I had sold my Mac 4 into 1 set up which was all basically in one piece, took the two bolts out per pipe and it all came off. I've seen set ups now that need flanges and or collars, no to mention flanges that bolt into the motor or flanges that clamp the sleeve on only. My question is what do I need to bolt this exhaust to my bike. Do I need the collars? Flange only? Etc. thanks