A unique water based, acrylic primer designed to block Patina Aging Solutions and Rust Activator from reaching the metal or wood surface chosen as a substrate. Other primers cannot be used because they allow the Patina Aging Solutions and Activators to penetrate through to the substrate. This will disrupt the desired patina color and damage the finish by bringing rust or tannic acids to the surface. ~~~ FEATURES: Unique water-based acrylic prime, Blocks Patina Aging Solution from surface. For use with Modern Masters Reactive Metallic Paints. Other primers cannot be used.