CUSTOM 421- Rust Proofing Body Primer

Rustbuster Custom 421 Epoxy Primer Paint


Custom 421 is the ideal primer for DIY enthusiasts and garages who lack the controlled environment of a professional body shop. Its excellent adherence to body panels and non-moisture absorbing properties means that it prevents panels from rusting - even if left for long periods before top coating. This is the main benefit of epoxy primer paint. 

Available in grey or red, Custom 421 can be filled with 2K body filler and overpainted with single or two pack paints.

How it works

The problem with traditional primers is that they are porous. If not overpainted within a relatively short period of time they will absorb moisture, leading to corrosion. But epoxy primer paint like Custom 421 is non-porous, so it can be applied and left for long periods. Simply abrade with a P320 abrasive prior to overpainting with a topcoat.

Custom 421 is typically sprayed but can also be brushed. It is supplied as a two-component pack, complete with thinners. The mix ratio is 4:1 by volume, plus thinners. Please follow the instructions to ensure best results.

Contact Rust

Rustbuster Ltd
Welland House
Cradge Bank
South Lincolnshire
PE11 3AN

01775 761 222

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Rustbuster is a registered trade mark of Rustbuster Ltd, registered in the UK Trademark number 2211446 Class 02 & 37.
Any unlawful use of the Rustbuster name or logo or passing off will result in legal proceedings. Rustbuster Ltd UK registerered 3639350.