You can’t spray it over rust and have it protect, it just reacts with the top layer. You have to remove the majority of therust firs for it to work. It won’t neutralize rust very far down, it is a paint that just sits on top and can’t penetrate very deeply.
Fluid-film can be sprayed over rust and will inhibit any further corrosion because it is in an oil carrier that penetrates deeply carrying the lanolin wasinto the pores of the corrosion and creates an oxygen and moisture barrier that shuts down the corrosion process.
