I used this stuff from Jamestown distributors...one part polyurethane.
http://www.totalboat.com/product/wet... AEgKBqfD_BwE
Use their primer first...you can sand, and prime, sand and prime, lightly sand until really smooth. then the top coat...look for their videos on the "roller and tip" method....won't be like an automotive pro spray job...but you can make a trailer look really nice...
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