POLL-Paint or undercoat?

Its called "Chassis saver" Same inventors of POR15 . Spray or brush it on over anything. Unlike POR15 it sticks to every thing not just the rust. And there are no pre wash solvents necessary. Spray it or brush it right out of the can. It even fills pinholes. Use fiber mesh and you can patch small holes. Good ****. Gets hard like a rock. it doesn't even glass bead off.