Gday.

I use Admil Professional N-195 Silicone because Ive found it's the best product that works for my clients. It's uses include automotive construction, masonry construction & exterior etc. This is a high quality product & long lasting. It's also great to work with - ie, smooth beads, easy clean up, fast cure etc.

Thats what I use on my own van and would recommend to anyone wanting to protect their gutters from rusting, for the practical use of the van (ie, out of the garage, driving in the rain...)

Mine was located 50mt's from the beach, at the mid coast; south of adelaide, and was constanty exposed to the salt in the air / and taken onto the beach weekly. Right now, it's under a tree. My gutters are fine.

Condensation causes cancer, it was a time consuming and expensive exercise to fix the rust on the inside of the roof. If you plan to use, have sex & sleep in your van, take my word for it! If your going to spray the thing, why not do a quality job, or you'll be back to square one within 4 season.

Cheers