Port window flange, what purpose?

[er9]

Iv'e been curious whats the purpose/function of the flange that sticks out from and rings some ports?

i was just cruising craigslist this morning and noticed them on this columbia.

https://sandiego.craigslist.org/csd/...465924085.html

My Bomar ports are similar and iv'e seen them on other boats as well. is it just a nautical style? Other than making the frame stronger and beefier and giving a little protection from rain coming in, im having a hard time figuring out their purpose.

[Suijin]

Those are replacement New Found Metals port lights. They come in two depths (to accommodate different cabin side thicknesses) and it looks like the owner chose the deep ones, which seems a bit odd. My flanges stick out about 1/4" from the sealing plates.

Some protrusion is good because it diverts water from collecting inside the port light, but that's excessive in my opinion. More to bang your calves and shins on.

[er9]

ah ok that makes sense. didnt think of that. mine stick out about .75 or so and keep the light drizzle out.