I have a pair of lightly used 4" diameter 8" long marine silencers (pipe containing baffles). They do not restrict flow and aren't overly quietquiet, but they take a lot of the harsh bark out of the exhaust sound.
I also have a pair of nice, 4" stainless steel exhaust tips with internal and external flappers. both internal metal flappers and external rubber flappers are in good shape for sale as well if you're looking to upgrade your boat to a through hull exhaust.
Let me know if you have any questions. Thanks!
do NOT contact me with unsolicited services or offers