Centek Vernalift Muffler 4.5" X 4.5" 12" X 12" Chamber.
The compact Vernalift muffler was designed for sailboat auxiliary propulsion engines installed near or below the water line.
These are "lift mufflers", incorporating an internal design which helps force the water out of the muffler without filling it, while markedly reducing exhaust noise.
If the engine exhaust manifold is near or below the waterline, a siphon break must be installed in the water supply line to prevent continued water flow after the engine is shut down.
When several body sizes are available, choose the largest that will fit the available space.
The increased volume will help ensure that residual water doesn't enter the engine after shutdown; the longer the exhaust system hoses, the more important this is.

Applications: powerboat, sailboat and generator engines
Fuel type: gas or diesel
Installation: above or below waterline, close to centerline - using proper practices
Sound rating: better
All models have square bases.