POR-15 Metal-Prep provides the best adhesion for POR-15 on any surface, including aluminum and shiny polished metal surfaces. The simple process gently etches metal, creating an ideal anchor pattern for coatings such as POR-15, while simultaneously leaving a zinc phosphate coating to ensure the chemical bonding of paint and steel. Avoid other preps that may leave harmful residues which prevent proper adhesion. After thoroughly degreasing work piece, apply environmentally safe Metal-Prep to neutralize any rust and etch any clean bare metal for better adhesion of POR-15 or other paint. Product is not caustic, corrosive, toxic, or flammable.