Johnstone's Professional Undercoat is a premium quality, alkyd based undercoat formulated for interior and exterior use on wood and metal surfaces. It provides the perfect surface for overcoating with Johnstone's Professional Gloss. Johnstone's Trade Professional Undercoat is a solvent-based undercoat paint that can be used for interior and exterior wood and metals. Transform your space with a stroke of colour and creativity with Johnstone's Trade Professional Brilliant White Undercoat 1L. This premium primer is formulated with high-quality solvents, making it perfect for preparing both interior and exterior wood and metal surfaces. Its versatility allows it to serve as an ideal undercoat for gloss, eggshell, or satin paints. With outstanding opacity, adhesion, and ease of application, it's a dependable choice for a wide range of projects. Additionally, its thick film build conceals imperfections effectively and creates a smooth surface that is perfect for sanding or finishing.