These undercoats can be used as a Sandable Primer, Sealer, or Surfacer to smooth rough finishes and mixed materials. These products feature an epoxy-based formula that is designed to protect composite and metal substrates from corrosion and chemicals, while providing excellent adhesion and consistency for ChromaGlast™ paint. Please review each product below and determine which is most suitable for your specific application. At FibreGlast.com, you'll find a selection of Paint Colors, Undercoats, and Additives. All ChromaGlast™ products are First Quality Guaranteed so you can work with confidence.