Penetrol makes it easy to control rust

What makes rust? Ordinary paint and primers "bridge" over the small imperfections found on any metal surface. Under this "bridge" air is trapped. Air contains moisture and this mixture of oxygen and hydrogen forms iron-hydroxide i.e. rust. Take one of them away and you eliminate rust. Under a microscope rust looks like a sponge full of air. Penetrol, due to its low surface tension will penetrate all the way through this sponge driving out the air and moisture and completely saturate the rust right down to the unattacked iron or steel. It has literally taken away the "food" rust needs to form and, by turning the existing rust into a protective coating, further rust formation is stopped and the paint is assured of 100% contact with the metal surface, the most important requirement for effective metal protection.

A drop of quality metal primer did not spread far or penetrate the rust. It sits on the surface trapping moisture and air beneath it. The same primer with 50% Penetrol spread many times further and deeply penetrated the rust displacing all moisture and air. Penetrol works and that's why it is used and recommended by people working in the roughest environment of all, the world's major shipping companies. Use Penetrol on structural steel, cast and wrought iron, wire fences, cars, trucks and trailers, corrugated iron, garden tools, tanks and anything made from ferrous or non-ferrous metal. Penetrol flows easily into crevices, welding seams, pipe joints and other areas that are hard to reach by brush, such as the inside of car doors.

Penetrol makes it easy to stop and prevent further rust
This is how easy it is to use Penetrol. Just saturate the rusted surface with Penetrol until it has a shiny appearance. When dry, continue with any oil, alkyd or water based paint. The main thing to remember about treating rust is that if you can't reach all areas of all surfaces, you're ultimately wasting your time.