if they are like mine....
when you open it up, go ahead and pull that black part away too, and give it a good look.
There's raw wood behind there and any leak through the foam gasket will cause rot.
They ended up replacing the entire back wall of my coach under warranty.
Then of course the things leaked again but I caught it. Resealed the fixtures with butyl tape and I have been keeping an eye on it....
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