very simpel,you take away the cathalisator and put a pipe holder who fits the 3 exhaust pipe's together instead of the catahalist,when you google and fill in triumph rocket 3 parts than you will find cathalist replacement , in the shop they ask 499 euro for is ,i become one on the internet 20 kilometers from my home for just 70 euro',it is stainless steel so it is still looks like new,i don't no how to put a picture here other wise i will show it to you.