Under Gone™

Under Gone™ Rust-Converting Undercoat for Vehicles & Equipment

Don’t just cover rust — convert it, then protect it. Under Gone™ is the only undercoating that corrects corrosion at the chemical level.

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Under Gone™
The Problem

Undercoatings aren’t fixing rust, they’re just slapping a band-aid on it!

Traditional undercoatings — whether lanolin, wax, or oil-based — simply cover existing rust without addressing the underlying corrosion. Moisture gets trapped underneath, and the rust continues to eat away at the metal from the inside out.

That means you’re paying good money to hide a problem that’s only getting worse.

The Under Gone™ Difference

Under Gone™ doesn’t just coat over rust — it chemically converts iron oxide into a stable, inert compound, then seals and protects the surface with a durable calcium sulfonate barrier. One product. Real protection.

Undercoatings aren’t fixing rust, they’re just slapping a band-aid on it!
Key Features

What Makes Under Gone™ Different

Engineered from the ground up to do what no other undercoating can — convert rust and protect metal at the chemical level.

Rust Converting Technology

Powered by a unique corrosion-correcting formula, Under Gone™ reacts with rust at the chemical level, converting it into a stable, inert compound.

Salt & Brine Barrier

Stops the #1 cause of corrosion: soluble chlorides from road salts and brine. Creates a tough barrier between your vehicle’s metal and the elements.

Advanced Adhesion & Longevity

Formulated with overbased calcium sulfonate that bonds tightly to metal surfaces for long-lasting, durable protection that won’t peel or flake.

Passivation & Protection

Goes beyond sealing — passivates the metal to halt corrosion activity and create a chemically inert surface that resists future oxidation.

Virtually Odorless & Easy to Apply

Goes on smooth and sets fast, unlike messy, smelly coatings. Suitable for professional shops and DIY users alike.

See How We Compare

Under Gone™ vs The Competition

Under Gone™ vs Fluid Film
Lanolin film vs. rubberized barrier
Under Gone™ vs Woolwax
Wool wax vs. rust-converting technology
Under Gone™ vs 3M Rubberized
Two rubberized coatings, one converts rust
Under Gone™ vs POR-15
Restoration coating vs. maintenance coating
See It In Action

Under Gone™ Videos

Watch how Under Gone™ converts rust and protects metal in real-world applications.

Under Gone™ FAQ

Frequently Asked Questions

Everything you need to know about Under Gone™ Undercoating.

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.
No, Under Gone™ is not a paint, and it won’t harden like one. It’s a water-based grease undercoating that lightly dries as the water evaporates, but it will always remain greasy to the touch. This is by design, as it forms a highly hydrophobic barrier that prevents salt and moisture from ever reaching the metal surface.
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 cure before heavy use. Annual inspection and touch-ups in high-wear areas are recommended for maximum longevity.
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.
Download the Under Gone™ Product Data Sheet (PDS)
Download the Under Gone™ Safety Data Sheet (SDS)

Ready to Protect Your Investment?

Stop hiding rust. Start converting it. Under Gone™ is the undercoating that actually works.

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