https://www.micmarineexhaust.com/productstags/3-inch-boat-exhaust-hose.html 3 Inch Boat ...    More ...

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3 Inch Boat Exhaust Hose
Wet exhaust systems are not uncommon on small horsepower engines on boats. A wet exhaust system is when water is injected into the exhaust system through a spray ring. This cools the hot exhaust gases and allows the use of a rubber hose downstream. The rubber exhaust hose usually has an inner metal wire that is wrapped like a spring to prevent the hose from collapsing if it is bent or something is placed on it. The advantage of a marine hose                over a metal exhaust system is that it is flexible, easy to install, and non-corrosive.

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