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RAPID SYSTEM 4:1:1 PRIMER HARDENER LITER - U-POL

Part #: 6401

The U-POL RAPID SYSTEM 4:1:1 Primer Hardener (Model 6401) is an essential component for professional automotive and industrial refinishing, designed to optimize workflow and deliver a high-quality finish. This 1-liter hardener is formulated with unique Rapid Cure Technology, significantly reducing cure times compared to conventional primer systems. It allows for increased throughput in the body shop by being ready to sand in under one hour, saving valuable time and energy costs.

Key Features

  • Rapid Cure Technology: Engineered for speed, this hardener enables the associated primer to be ready for sanding in less than one hour, accelerating repair cycles.
  • Versatile Mixing Ratios: Integral to the Rapid System Primer, this hardener facilitates a 4:1:1 (primer:hardener:reducer) mix ratio for use as a primer surfacer, or other ratios to function as a high-build primer filler or sealer.
  • Excellent Foundation: Provides superior hiding capabilities and excellent coverage, ensuring a uniform and high-quality foundation for subsequent color coats.
  • Easy to Use and Sand: Designed for straightforward application and offers easy sanding properties, both wet and dry, to achieve a smooth surface.
  • Universal Hardener: Only one hardener is required for all climates and conditions, simplifying inventory management and reducing stock investment for repair facilities.
  • Tintable Compatibility: The associated Rapid System Primer can be tinted with up to 10% basecoat, allowing for enhanced color matching and reduced basecoat consumption.

Applications

This U-POL Rapid System Hardener is ideal for professional technicians and mechanics engaged in automotive collision repair and industrial coating applications. It is suitable for preparing a wide range of substrates, including bare steel, aluminum (with recommended acid etch primer), galvanized metal (with recommended acid etch primer), original paint, body filler, GRP, SMC, fiberglass, and most plastics. Its fast-drying nature makes it particularly beneficial for both spot repairs and larger multi-panel jobs where efficiency is crucial.

Only 4 left in stock - order soon Inventory available from other suppliers, prices may be different

$50.11

Free shipping on orders over $250
Lower 48 states and DC. Excludes freight and oversize items.
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  • Model: 459935
  • Shipping Weight: 2.5lbs
  • UPC: 5010796110314
  • Manufacturers Part #: 6401
  • Manufactured by: U-POL
  • Also Known As: UP6401, UPO6401

This product was added to our catalog on Monday 08 June, 2026.

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