I have no personal experience with POR-15, but it seems to be some good stuff. When I had my old '63 Tri-Power Bonneville, I was going to use it on the rusted trunk floor. Until a lowrider in a '64 Impala took me out on the freeway. I miss that car.bob b said:paulo 57509 do you know if the product Por-15 actually works? I would like to try such a product on developing rust spots.