My V@H Duals were way too loud so I went out and got the quiet baffles that helped a bit but not as much as i wanted, I went the Daalder Exhaust In Dandenong and he suggest this set up. Gas goes in the silver side, at the end it's blocked.The gas is forced through the little holes to disperse airlfow, then the gas goes down the larger holes in the black part and then out . The long black part is wrapped in sound deadening material. They are the entire lenght of the rear tubes. It's really good. Nice deep rumble without the "crack" explosions. It would still never pass a test but now I won't give the next doors the shits either. Cost bugger all and the guys were really good too. Took it for a spin and they are now not intrusive in your helmet when you ride. Any one got any other suggestions that may bring the sound down without chocking the bike to death?