Krud Kutter The Must for Rust is a superior rust remover and inhibitor. The proprietary formulation penetrates into every void of a metal surface and dissolves rust/oxidation through chemical action. Then tiny, rust-inhibiting crystals are formed and become integral with the surface molecules of the metal to resist future rusting. The corrosive agents attack these crystals instead of the metal. Once completely dry, the surface is ready for the next step, whether it be painting, welding, plating, lubricating, etc. Or simply leave the surface bare, and the crystals will inhibit future rust formation.