Introducing Under Gone™

The first rust converting undercoat. Don't just cover rust, convert it, then protect it.

You hear it all the time: “Undercoatings aren’t fixing rust, they’re just slapping a band-aid on it!” That’s where Under Gone™ changes the game.

Like any quality undercoating, Under Gone™ provides a tough barrier against salt and brine. But it doesn’t stop there. Under Gone™ goes further by actively converting existing rust into a stable layer and passivating the surface underneath. That means it not only protects but also corrects—addressing the root of the problem instead of just covering it up.

Rust Converting Technology – Powered by a unique corrosion-correcting formula, Under Gone™ reacts with rust at the chemical level to stabilize it into a protective layer.
Salt & Brine Barrier – Stops the #1 cause of corrosion: soluble chlorides from road salts and brine. Once applied, your vehicle is shielded from winter’s harshest conditions.
Advanced Adhesion & Longevity – Formulated with overbased calcium sulfonate, Under Gone™ bonds tightly to metal surfaces and forms a durable, self-healing film. Calcium sulfonate resists wash-off, remains stable under heat and pressure, and provides natural corrosion inhibition. This chemistry not only locks out salt, brine, and moisture but also delivers staying power for long-term protection.
Passivation & Protection – Goes beyond sealing; it passivates the metal to halt corrosion activity while leaving a strong, protective coating.
Virtually Odorless & Easy to Apply – Unlike other messy, smelly coatings, Under Gone™ goes on smooth and sets fast. Application is simple: remove loose rust, rinse with Salts Gone®, then apply Under Gone™.

FAQs

Under Gone™ is a Rust Converting Salt Barrier that not only protects your vehicle from corrosion but also chemically converts existing rust into a stable, protective layer (it actually passivates metal).

Under Gone™ uses advanced calcium sulfonate chemistry with conventional rust converters to react with rust at the surface, stabilizing it into an inert layer. This process both halts further corrosion and creates a base for the protective barrier that blocks salt, brine, and moisture.

Traditional coatings mainly cover rust without stopping its spread. Under Gone™ stands out because it is a rust converter and corrosion inhibitor in one, delivering stronger adhesion, better salt resistance, and longer-lasting performance under harsh driving conditions.

Yes. Under Gone™ is specifically designed to convert and stabilize existing rust before sealing it. For best results, remove loose or flaking rust and rinse with Salts Gone® to eliminate soluble chlorides prior to application.

Under Gone™ can be applied using an undercoating gun, sprayer, or brush. Simply prep the surface and apply evenly.

Under Gone™ is built for long-term adhesion and durability, resisting wash-off, heat, and pressure. The product should be allowed to dry before being exposed to the elements. It should be inspected annually and touched up as needed, especially in high-wash areas.

Yes. Unlike strong-smelling lanolin or solvent-based coatings, Under Gone™ is virtually odorless and safe to use in a garage or shop setting with standard ventilation.

Absolutely. Under Gone™ is ideal for trailers, off-road vehicles, farm equipment, fleets, and classic cars — anywhere rust and salt exposure is a concern.

Under Gone™ is available in 1 gallon, 5 gallon pails, and 55 gallon drums, making it ideal for DIY users, automotive shops, and fleet operators alike.

Under Gone™ is manufactured in Houston, Texas, USA by Custom Chemicals & Coatings. We take pride in producing high-quality, American-made undercoating solutions that deliver real results.