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RP-342 "HEAVY" Military-Grade Rust Preventive Spray

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  • Cosmoline Military Grade RP-342 Heavy Aerosol Spray | Cosmoline Direct
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  • Cosmoline Military Grade RP-342 Heavy Aerosol Spray w/ Straw | Cosmoline Direct
  • RP-342 "Heavy" Aerosol (3-Pack)
  • Cosmoline RP-342 - 100% Satisfaction Guarantee!
Ships UPS Ground (excluding HI & AK)
IN-STOCK. Ships Same Day (when order placed before 4:30pm EST).

Cosmoline RP-342 "Heavy" Military-Grade Rust Preventive Spray   (12 oz. Aerosol Spray Cans)

Our Strongest, Longest-Lasting (and Fastest-Drying) Rust Preventive Aerosol, PERIOD!

   *  Offers the highest concentration of Industrial-Grade Cosmoline® available in a convenient Aerosol Can.
   *  1-coat protects all metals, iron, steel (stored Indoors or Outdoors) for Years!
   *  Newly formulated!  Our thickest, longest-lasting Rust Preventive Spray.
   *  Produces dry-to-the-touch, amber translucent (see-through) petroleum wax coating.
   *  Faster-Drying formula allows for quicker handling and/or shipping.
   *  Withstands severe outdoor exposure, salt-laden atmospheres, acid & caustic fumes and other damaging environs.
   *  Repels water and will not wash off in salt water environments.
   *  Will not crack, craze, peel or flake and remains slightly flexible over time.
   *  Exceptional Vehicle Undercoating Product (Autos, Trucks, Buses, Trailers, etc.) - Road salt, debris and chemicals - No Problem!
   *  Aggressively adheres to imperfect surfaces and offers self-abraiding characteristics.
   *  Modeled after Military Specifications:  MIL-PRF-16173, Grade 4 and MIL-C-83933.
   *  Trusted since World War II.  Our Bestselling Aerosol - commercial customers, US Armed Forces, Government & Do-it-Yourselfers.
   *  Your Satisfaction with this product is Guaranteed!*

This Bestseller is now available in Bulk (gallons and 5-gallon pails)!   Learn More

COMMON APPLICATIONS INCLUDE (but are not limited to):

   *  Vehicle undercarriage / undercoating (cars, buses, trucks, etc.) - Extremely effective!  - See RP-342 Undercoating FAQs.
   *  Parts & equipment storage  
   *  Overseas transportation
   *  Heavy machinery & equipment
   *  Packaging
   *  Dies, molds, lathes, shafts and beams
   *  Offshore Drilling equipment, platforms & infrastructure
   *  Farm implements   
   *  Boat shafts and propellers
   *  Marine fittings
   *  Rifle & other firearms preservation/storage
   *  Garden tools
   *  Lawn mower blades
   *  and any other surface or part that might rust on you...

DOWNLOADS:  Product Data Sheet / Overview     RP-342 Safety Data Sheet (SDS)        

All aerosol cans come with 6-inch extension straws which allow you to apply product in hard-to-reach surfaces, crevices, gaps, cavities, etc.
* The RP-342 aerosol can spray while upside down, sideways and of course, right side up....which makes getting the hard-to-reach spots much easier.

VEHICLE UNDERCOATING USAGE APPROXIMATIONS (for thorough, heavy application):
Mid-Size Sedan:  6 Aerosol Cans for Undercarriage.  Add 3 Aerosol Cans for Inside Door Panels, Tailgate, etc.. 

Full-Size Truck:  6-9 Aerosol Cans for Undercarriage.  Add 3 Aerosol Cans for Inside Door Panels, Tailgate, etc.. 
* In both scenarios, you'll likely have an extra can or two.  However, it's better to have a little too much than run out.  
** The RP-342 aerosol can can spray while upside down, sideways and of course, right side up.  Makes for getting the hard-to-reach spots much easier.

Make sure surface is reasonably clean and dry. Spray thin uniform film.  For more very long storage durations, a second coating can be applied if desired within 30 minutes.  Complete setting of protective coating takes approximately 1-2 hours after spraying.  Typical first application Dry Film Thickness is 2.0 Mils (51 Microns)

RP-342 "HEAVY" can be easily removed with any over-the-counter petroleum solvent. Examples include mineral spirits, paint thinner, naphtha, diesel fuel, or our very own Cosmoline Remover.  Our Cosmoline Remover is very effective, but also considerably more expensive than the other options mentioned.

RP-342 "HEAVY" is modeled after the following military specifications: MIL-PRF-16173E Grade 4, Class 1 and MIL-C-83933

* Certificates of Conformance are not available for this product. 

2 years when stored in prudent conditions (cool, dry, shaded).

* Ozone Depleting Substances - Aerosol products were not manufactured, do not contain, and were not packaged using any Class 1 or Class 2 ozone depleting substances as defined by the clean air act.  
* Non-Chlorinated (no chlorinated solvents).


 Product Videos

Cosmoline RP-342 - Vehicle Undercoating Overview
  • Cosmoline RP-342 - Vehicle Undercoating Overview
    Showcasing Cosmoline RP-342 (Military-Grade) Vehicle Undercoat...

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