System 20 National Rule Slow Hardener is compatible with both System 20 National Rule Primers and System 20 National Rule Clearcoats. The end result: An easy-to-use system with less products to stock. Product Features:Compatible with 4:1 System 20 National Rule PrimersCompatible with 4:1 and 2:1 System 20 National Rule ClearcoatsIdeal for large repairs and high temperatures
