That’s Mister Chalet To You ....
The very first minute of this video is the guy I bought the bike from explaining that there's no available DB killer for this exhaust and that a normal slip-on can't be fitted because the exhaust tapers-out small to large in this limited edition exhaust. Hence: technical differences from the standard exhaust.
And to quote someone whose opinion I trust and believe:
I prefer stock condition when buying used,but this bike has BST's,the rare as hen's teeth,impossible-to-find-anywhere Akra full Ti Evo 2