🛡️ Soft, Self-Healing Rust Protection That Keeps Working

Protect your vehicle with a corrosion-control system designed to creep into seams, address existing rust, and remain soft and active over time.

The Under Gone™ Soft-Coat Rust Protection Kit gives you everything needed to prep and protect a typical vehicle with a soft, flexible undercoating designed for frames, chassis components, seams, cavities, and other rust-prone areas.

Unlike hard coatings that cure into a rigid shell, Under Gone™ remains soft and self-healing, allowing it to creep into difficult-to-reach areas and flow back over surfaces that may be disturbed by road debris or normal vehicle use.

And unlike many traditional soft undercoatings that simply cover existing corrosion, Under Gone™ also helps chemically convert and stabilize existing surface rust while leaving behind a calcium-sulfonate-based protective barrier.

The result is an easy-to-apply rustproofing system designed for trucks, cars, trailers, work vehicles, equipment, and other metal surfaces regularly exposed to moisture, road salt, and harsh environments.

The Under Gone™ Protection Process

PREP → SPRAY → PROTECT

PREP: Remove road salt, brine, and corrosive contamination with Salts Gone®.

SPRAY: Apply Under Gone™ to the frame, underbody, seams, cavities, and other rust-prone metal surfaces.

PROTECT: Under Gone™ helps treat existing surface rust while leaving behind a soft, creeping, self-healing corrosion barrier that stays active over time.

Simple application. Serious rust protection.

⭐ Why Choose Under Gone™?

• Converts & Protects: Helps chemically address existing surface rust instead of simply covering it.

• Soft & Self-Healing: Remains flexible and can flow back over areas disturbed by road debris, vibration, or normal use.

• Creeps Into Hard-to-Reach Areas: Designed to penetrate seams, crevices, boxed sections, and other areas where corrosion often begins.

• Calcium Sulfonate Protection: Creates a corrosion-resistant barrier designed to help protect steel from moisture and environmental exposure.

• Won't Cure Into a Hard Shell: Stays soft and active instead of becoming rigid or brittle.

• Easy to Inspect & Maintain: The coating can be checked, touched up, and refreshed over time as needed.

• Designed for Harsh Environments: Helps protect against road salt, brine, moisture, oxygen, and other common causes of corrosion.

• Complete Vehicle System: Includes the coating, surface-prep solution, applicator gun, and extension hoses needed for a thorough application.

📦 What's Included

8 Quarts of Under Gone™ Rust-Converting Undercoating

A full 2 gallons of Under Gone™ for protecting frames, chassis components, seams, cavities, and other corrosion-prone areas.

Under Gone™ combines rust-converting chemistry with a soft, calcium-sulfonate-based protective barrier designed to remain active after application.

Undercoating Applicator Gun

Provides controlled spray application for coating broad areas of the frame and underbody.

Spray Gun Extension Hoses

Reach deeper into boxed frames, cavities, channels, seams, and other difficult-to-access areas where corrosion can begin long before it becomes visible from the outside.

Salts Gone® Hose End Sprayer

Proper rust protection starts with proper preparation.

Salts Gone® helps remove road salt, brine, and other corrosive salt contamination before Under Gone™ is applied, helping prevent those contaminants from becoming trapped beneath the protective coating.

🚙 How Much Will One Kit Cover?

One Kit Is Designed for One Typical Vehicle

This kit is intentionally sized to provide enough material for a typical passenger vehicle or pickup truck.

With 8 quarts — 2 full gallons — of Under Gone™, you'll have material for broad frame and underbody coverage as well as seams, cavities, and hard-to-reach areas.

Exact coverage will vary depending on:

• Vehicle size

• Amount of surface area being coated

• Application thickness

• Existing surface condition

• Overspray

• How extensively internal cavities and boxed sections are treated

For a typical passenger vehicle or pickup truck, one complete kit should provide the material needed for a thorough application.

Extra-large trucks, commercial vehicles, or unusually extensive applications may require additional material.

🔧 How to Apply the Under Gone™ System

STEP 1 — Prep With Salts Gone®

Long-lasting rust protection starts with a properly prepared surface.

Use the included Salts Gone® Hose End Sprayer to thoroughly wash areas that will be coated, helping remove road salt, brine, and other corrosive salt contamination.

This is especially important on vehicles that have been driven in winter conditions or regularly exposed to salt.

Allow the surface to properly dry before applying Under Gone™.

STEP 2 — Apply Under Gone™

Use the included applicator gun to spray Under Gone™ onto the areas you want to protect.

Focus on corrosion-prone areas such as:

• Frames and chassis components

• Crossmembers

• Suspension mounting areas

• Wheel wells

• Seams and overlapping metal

• Welded areas

• Brackets and supports

• Boxed frame sections

• Internal cavities and channels

Use the included extension hoses to reach inside enclosed areas where conventional spray patterns cannot easily reach.

Because Under Gone™ remains soft, it can creep into seams and irregular surfaces after application instead of simply sitting as a rigid coating on top of the metal.

STEP 3 — Let Under Gone™ Keep Working

Under Gone™ is intentionally different from a traditional paint or hard undercoating.

It does not cure into a hard shell.

Instead, it remains soft and active, helping maintain a protective barrier while allowing the coating to move, creep, and self-heal over time.

Because it remains accessible, the coating can also be inspected, touched up, or refreshed in the future as needed.

Why Under Gone™ Is Different

Many conventional soft rustproofing products are designed primarily to create a moisture barrier over the metal.

Under Gone™ takes a different approach.

It Helps Address the Rust That's Already There

Under Gone™ incorporates rust-converting chemistry designed to help chemically react with and stabilize existing surface rust.

Then It Protects the Surface

After application, the calcium-sulfonate-based coating remains soft and provides an active barrier between the metal and the moisture, salt, oxygen, and environmental exposure that contribute to continued corrosion.

And It Stays Active

Because the coating does not cure into a rigid shell, it can continue creeping into seams and hard-to-reach areas while maintaining the soft, self-healing characteristics many vehicle owners prefer from a rustproofing undercoating.

Convert. Protect. Maintain.

Soft-Coat or Hard-Coat — Which Is Right for You?

Salts Gone® offers two different approaches to vehicle rust protection because not every customer wants the same type of coating.

Choose Under Gone™ Soft-Coat Protection If You Want:

• A soft, flexible rustproofing coating

• Self-healing protection

• A coating that creeps into seams and cavities

• Rust-converting chemistry built into the undercoating

• Easy future inspection and touch-ups

• Protection that remains active instead of curing hard

Choose a Thixo-Coat® Hard-Coat System If You Want:

• A hard, cured protective finish

• Zinc-enhanced corrosion protection

• Greater resistance to abrasion and impact

• A painted, semi-gloss finished appearance

• A rigid long-term coating system

Soft or hard, the right system depends on how you want your vehicle protected.

Ideal Applications

The Under Gone™ Soft-Coat Rust Protection Kit is ideal for:

• Pickup trucks

• Passenger vehicles

• Work trucks

• SUVs

• Vehicle frames and chassis

• Utility trailers

• Equipment trailers

• Marine trailers

• Agricultural equipment

• Construction equipment

• Restoration projects

• Fleet vehicles

• Off-road vehicles

• Other steel surfaces exposed to moisture, road salt, and corrosive environments

🛡️ Don't Just Cover Rust. Convert It. Protect It.

Rust often starts in the places you can't easily see — inside seams, around overlapping metal, within boxed frame sections, and in areas repeatedly exposed to moisture and road salt.

Under Gone™ is designed to go after those areas with a different kind of rust protection.

Wash away the salt.
Address the existing rust.
Spray the areas corrosion attacks first.
Leave behind a soft, active protective barrier.

The Under Gone™ Soft-Coat Rust Protection Kit brings the entire process together in one convenient package, giving you the products and application tools needed to protect a typical vehicle from the places you can see to the places you can't.