Same black skin as stock, but with more rust.
Excerpt from 'Pigboat 39'
Then when the boat came out of the navy yard after overhaul, ready to make her deep dive to see if her hull was tight, the skipper and the inspection officer were concerned because leaks were reported all over the boat. Pop Bridges, whose experience nobody could question, smiled his wise little smile and said, "Don't worry sir. They all leak at first. Give her some time to rust up. It's a riveted hull, and after she shakes down for about a month there'll be no more leaks"
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