Reach for a Can of Rust Penetrant for That Seized Bolt

If you're looking for a way to get through those tough rusty bolts, you need a rust penetrant! Check out our list of the five best rust penetrants, and never worry about a stuck bolt again!

Rust penetrants are chemical solutions designed to penetrate the rust layers and loosen them up for easy removal. When applied correctly, they can help break down rust particles and make them easier to clean off surfaces.

Rust penetrants work by dissolving the bonds between the iron molecules that make up the rust layer, making it easier to remove without causing damage to surrounding materials.

How Mechanicaddicts Chooses the Rust Penetrant

At Mechanicaddicts, we put a lot of time into researching and testing different rust penetrants to ensure we offer our customers the highest quality. We base our decisions on price, performance, safety, environmental impact, and customer feedback.

Free All Rust Eater Deep Penetrating Oil

Check Price

Why We Like This Product

Free All Rust Eater is a breakthrough deep penetrating oil that quickly and easily frees up parts and assemblies affected by rust, scale, corrosion, red and white lead, tar, grease, carbon, and graphite deposits.

No more tedious and time-consuming hammering or chiseling – this powerful solution instantly loosens pipe connections, rusted screws, bolts, and clamps. Free All Rust Eater is also safe to use in paint shops or other environments where silicones are not desired.

About this item:

  • Flash Point: 25 Degrees Celsius
  • Material: Graphite
  • Brand: Gasoila
  • Package Information: Can
  • Liquid Volume: 11 Fluid Ounces
  • Item Weight: 11 Ounces

WD-40 Specialist Penetrant

Check Price

Why We Like This Product

The WD-40 Specialist Penetrant is a powerful tool designed to combat rust and corrosion in various applications. Equipped with a Smart Straw nozzle, this premier product offers precise spray control, allowing for broad coverage and concentrated streams.

It features a low-odor formula that profoundly penetrates crevices, threads, and seams to disrupt the bonds holding stuck parts together, making it perfect for tackling rusted or seized nuts, bolts, threads, locks, and chains.

The WD-40 Specialist Penetrant is safe for use on metal, rubber, and plastic parts and complies with all 50 states' VOC regulations. The fast-acting formula not only works on contact but also leaves behind a protective layer to inhibit the reformation of rust and corrosion.

As a product under the WD-40 Brand, known for its high-quality solutions, professionals trust this penetrant to perform reliably even under extreme conditions. The WD-40 comes with an ez-reach flexible straw and can access hard-to-reach places on seized equipment fasteners and keep your parts safe from future corrosion.

About this item:

  • Flash Point: 40 Degrees Celsius
  • Brand: WD-40
  • Liquid Volume: 11 Fluid Ounces
  • Item Weight: 11 Ounces
  • Recommended Uses For Product: Industrial

CRC Screwloose Super Penetrant

Check Price

Why We Like This Product

Unleash the power of the CRC Screwloose Super Penetrant, a product of CRC Industries, a recognized leader in the chemical solutions industry renowned for its exceptional quality and performance.

Specifically designed to combat corrosion, this concentrated solvent acts promptly and powerfully to liberate fasteners and other mechanical components held captive by rust.

Thanks to its petroleum distillate base, its high-quality formula promises effective penetration, even in the tightest and most intricate crevices. Notably, the oil is safe for all plastics, ensuring versatility in its applications.

From nuts and bolts to pins, screws, bushings, clips, hinges, snaps, lugs, caps, locks, washers, and sliding mechanisms, the Screwloose Super Penetrant has got you covered. Available in a convenient 11 wt oz. Aerosol can it's a must-have addition to your maintenance toolkit.

About this item:

  • Flash Point: 61 Degrees Celsius
  • Brand: CRC
  • Liquid Volume: 470 Milliliters
  • Item Form: Aerosol
  • Recommended Uses For Product: Mechanical, Electrical

CorrosionX Corrosion Technologies 91002

Check Price

Why We Like This Product

CorrosionX Corrosion Technologies 91002 offers revolutionary solutions to rust and corrosion with its unique Polar Bonding and Fluid Thin Film Coating (FTFC) technologies. This breakthrough lubricant sticks to metal like a magnet, providing superior resistance to displacement by friction or pressure while also lubricating under extreme loads and high temperatures.

On top of that, this fantastic penetrant and anti-seize works quickly to break free rusted nuts, bolts, and fittings within minutes. And not only that, it’s safe on electronics, displacing moisture and protecting electronics with a self-healing high dielectric Fluid Thin Film Coating that won’t interfere with circuits with its zero VOC formulation.

About this item:

  • Flash Point: 143 Degrees Celsius
  • Material: oil-based lubricant
  • Brand: CorrosionX
  • Liquid Volume: 16 Fluid Ounces
  • Item Weight: 1.05 Pounds
  • Recommended Uses For Product: Lubricant, Industrial

Liquid Wrench Gunk L112/6 Super Penetrant Spray

Check Price

Why We Like This Product

Liquid Wrench Gunk L112/6 Super Penetrant Spray is a powerful, versatile multi-use penetrating lubricant that helps loosen rusted, corroded nuts and bolts. Its 11 oz aerosol spray contains a solid block desiccant core made of molecular sieve and activated carbon that helps break through rust.

The product also features an easy-to-use spray straw for precise and consistent application. It is manufactured in the United States, making it an excellent choice for those looking to support local businesses while achieving superior results.

This penetrating lubricant from Liquid Wrench will help you quickly free up stubbornly stuck components, freeing up your time to focus on other tasks.

About this item:

  • Flash Point: ‎56 Degrees Celsius
  • Material: Liquid
  • Brand: Liquid Wrench
  • Package Information: Bottle
  • Liquid Volume: 11 Fluid Ounces

Rust Penetrant FAQs:

1. What Is a Rust Penetrant?

A rust penetrant is a chemical treatment that helps to penetrate and dislodge rust on metal surfaces, making them easier to clean or repair. Rust penetrants loosen the bond between the rusty surface and the metal beneath it. 

This action allows for more effective cleaning and protection from further corrosion. In addition, rust penetrants can also be used as a preventive measure to protect metal surfaces from the formation of rust in the first place.

2. What Are Some Common Uses for Rust Penetrants?

Rust and corrosion penetrants are commonly used on cars and other vehicles to help prevent corrosion and improve the appearance of aging vehicles. 

Rust penetrants can also be used on tools and other metal objects to help protect them from premature corrosion and make them easier to clean or repair.

3. What Are the Benefits of Using a Rust Penetrant?

The main benefit of using a rust penetrant is that it can help prevent further corrosion of metal surfaces, extending the life of a vehicle or tool. Rust penetrants can also make cleaning rusty metal surfaces easier and improve appearance.

4. Are There Any Risks Associated With Using Rust Penetrant?

As with any chemical treatment, there is always some risk associated with using rust penetrants. It is essential to carefully read and follow all directions when using a rust penetrant to minimize potential harm. In addition, it is essential to wear protective clothing, such as gloves and goggles, when applying rust penetrants.

5. Is Rust Penetrant the Same as WD-40?

No, rust penetrant is not the same as WD-40. Rust penetrant is designed to penetrate rusted metal surfaces and loosen them up. At the same time, WD-40 is a multi-purpose lubricant and protectant that can be used for various tasks, including rust prevention and plastic parts ideal situations.

6. What Is a Nail Climb Test Performed at a Technical Center?

A nail climb test is an essential technical procedure in an engineering laboratory's technical center to determine the relative ability of a protective coating or other surface treatment to prevent rust penetration. 

The procedure involves placing a treated metal sample on an inclined board, which is then covered with nails. A specified weight is placed onto the nails and left for a given time period. 

After the specified time, the pins are removed and inspected to see if any rust penetrant has leached onto them. WD-40 completes these specific tests at a test center in (Pine Brook, NJ) and the product will have a test date on the can.

Final Thoughts About Rust Penetrant

Rust penetrant is an excellent tool for preventing rust and corrosion on metal surfaces. It can be applied to avoid rust in a variety of conditions, both indoors and outdoors.

Rust inhibitor is easy to use with minimal effort and provides lasting protection from corrosive agents. It's cost-effectiveness and long-term protection make it an excellent choice for anyone looking to protect their metal surfaces from rust and corrosion.

Using a rust penetrant is an easy way to preserve the life of your metal items and keep them looking great for years. So if you're looking for an effective way to prevent rust and corrosion, try rust penetrant! It's one of the most straightforward, affordable solutions around.

Thank you for reading!

Your friend,


Lubricate Just About Anything With Silicone Spray
Stop squeaks and rust in their tracks with our roundup of the best silicone spray! This spray is the ultimate secret weapon for any DIYer, from lubricating doors and hinges to protecting metal surfaces.
Are you looking for the best products? We've got you covered! Our editors independently selected each item on this list. Mechanicaddicts may collect a share of sales or other compensation (at no cost to you) from links found within these pages if they choose to buy something (that's how we stay in business); as an Amazon Associate, we earn from qualifying purchases. Reviews have been edited for length and clarity; enjoy finding your next favorite thing today!