Restoring nuts and bolts?

I use this stuff called evaporust all you do is put them in there and let them sit it does the rest.
http://www.forabodiesonly.com/mopar/showthread.php?t=75828&page=5
Here are some before and after shots


I skimmed through those posts and that stuff looks great.

Now the question is will those parts rust again, or does it leave some sort of protective coating.