The rust protection for POR-15 is not affected by the sun.
But the sun will change its appearance cosmetically from a
glossy black to a matte black (and it can be an inconsistant
matte black). That's they recommend you topcoat it.

I have straight POR-15 on my bush bumpers and I like the
matte black look...

Thanks,
Chris

---- Original message ----
>Date: Fri, 11 Jul 2003 01:17:31 +0000
>From: karen davis <yosemite333@HOTMAIL.COM>
>Subject: por 15
>To: vanagon@GERRY.VANAGON.COM
>
>Is it true that you can't leave this on your auto without a
topcoat if it
>gets sun as rays will damage?
>
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