300-series stainless steel is highly resistant to rusting. It’s the iron particles in the air, called fallout, mostly from brake rotors, that land on the bare steel causing a chemical reaction which makes it rust. The iron particle that is, not the stainless steel. It’s surface contamination that can be cleaned off. It causes no damage to the body itself.
When the stainless steel doesn’t make your car rust proof, so you explore alternatives.
300-series stainless steel is highly resistant to rusting. It’s the iron particles in the air, called fallout, mostly from brake rotors, that land on the bare steel causing a chemical reaction which makes it rust. The iron particle that is, not the stainless steel. It’s surface contamination that can be cleaned off. It causes no damage to the body itself.
It won’t be rust resistant when it hits the salty winter streets in a few months lol