I just got my Rokktech muffler and was surprised to see how it was designed!!

The muffler is 48" long and 8.5 inches in diameter, even though its 8.5 inches in diameter the 4" pipe goes straight through the muffler, no baffles or perforations with the exception of 4 - 2"x2" square holes cut into the 4" pipe right at the outlet, the rest is straight pipe. They are claiming near stock sound levels, hard to believe that those 2"x2" square holes cancel out the exhaust note that effectively???

Weirdest muffler design I have seen yet, but its also the first diesel muffler I have seen as well.

 

I also looked inside of one that I bought, and it was very interesting. I do believe what they say about them, though, very quiet

 

Was that a Rokktech or one of your Flo Pro's

 

Mine's straight through, about 4" in diameter, no baffles, perforations, holes, nothing. Just a nice, straight, piece of pipe.