Permatex spray-on rust treatment is claimed to displace rust and prevent new rust from forming. It can also be brushed on by spraying some in a cup or the cap. The spray is nearly clear, and turns the ...

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? An ominous brown stain on the fender. A bubble in the paint at the bottom of a door.