SuperTrapp muffler discs

I have 2 small clamp-on SuperTrap units that I bought out of the VW EMPI catalogue a few years ago. When I need to have less noise (like when I drive in Beverly Hills), The 12 disc tips clamp on to any pair of 2" tailpipes in a couple of minutes and make a considerable reduction in sound. Larger or smaller pipes sizes could be accommodated by any muffler shop. I'm also real happy with my stand-alone ST muffler/spark arrester on my Maico 450 dirt bike. I have played with different numbers of discs. Not a whole lot of difference in power or sound noticed with 10 or more discs. Never experimented on a dyno. on the Maico or my Barracudas, (318, 340 and 440).